Heyo!
Since there's a lot of discussion about the Ballot Fighters 4Chan rumor VS. the Shovel Knight rumor, I'd like to present my theory. I'm aware that this is already treaded ground, but there's a lot of black-and-white viewing going on right now, so I'd like to try and bring the shades of grey in between (inb4 non-relevant 50 Shades joke) to the forefront, if for nothing else than for more healthy discussion and debate. I'll also be speaking from the assumption that these rumors are true.
So, to begin, I'd like to clear up this misconception that both rumors somehow can't coexist and if there's any legitimacy to them only one can be true and the other fake. Basically, the misconception that they're mutually exclusive.
Because they're not.
First off, nowhere in the 4chan rumor was it ever stated that there weren't more characters. Keep in mind, the specific phrasing used was that the leaker "heard information about the upcoming ballot DLC". Ballot DLC. The first three planned Ballot characters. Not only does that not bar the possibility for more later on (If character packs are still 4 characters each, then I can see 3 more, I'll explain why later on), it also fails to account for the two pre-ballot slots that have been in planning since Mewtwo was added.
Everything we've heard about Shovel Knight, to my knowledge, suggests that he is a pre-ballot character, having been worked on for a while. Being pre-ballot, he is in no danger of having all the evidence points towards his inclusion automatically discredited because a 4chan leak describing post-ballot characters doesn't include him as a pre-ballot character. On the same token, the Shovel Knight rumor doesn't discredit the 4chan leak because Shovel Knight is pre-ballot, has been in planning for a while, and we've only heard about the ballot DLC within the last month while The SK rumor has been around for a while longer and was in part based off of, IIRC, Amazon insider info rather than sources within or close to Nintendo workers, making it understandable that Tama wouldn't have any info on other characters.
Now, with that misconception cleared up, we have a minimum of five characters coming - two pre-ballot and three post-ballot. Now, there's a few reasons for me saying this. The biggest reason, of course, is the two 'Mario' slots. They've been there in the coding since Mewtwo, suggesting that the characters that will eventually take their spot have been at lest planned since the time Lucas, Roy, and Ryu were being worked on. And while some have already presented the thought that the slots were just debugging test slots or unused space, this doesn't make since when we look at the third a lot added with the new patch. No matter what the use is, they wouldn't add a third slot unless they were planning to use it, meaning we have at least three characters. But if they're planing a third character, that means they already were planning a first and second character for the two slots. I understand that some may counter that the slots could be empty and all three are just for the Ballot DLC, but I've said it before here and I'll say it again: if they can add new slots as any time, especially as evidenced now by the addition of another slot, there's absolutely no reason Nintendo would have jumped the shark and added two post-ballot slots to their coding if they were just gonna sit on them for six months until the ballot ended. Those slots were there because they were already assigned to characters, so any slots we get beyond those are definitely Ballot DLC. Which makes two pre-ballot, and with the Ballot DLC added three, that makes five.
'But wait,' you may be asking, 'why weren't there three slots added then?' A very good question, and I would never have the answer obviously, so I can only work with the facts (and the assumption for the purposes of this post that both rumors are legit). How I see it is that the newly-added a lot belongs to Wolf. Why? Because he's the easiest to make. As mentioned by the 4chan leak, Wolf was already being seriously considered for pre-ballot DLC, but it was his super high placing in the ballot itself that solidified his chances for being made DLC, albeit as a ballot choice. Being a veteran and a semi-clone in the same way as Lucas, Wolf would be, especially
In comparison to Bomberman and K. Rool, extremely quick and easy to make. Lucas was also basically completely done by the time they revealed him as evidenced by how complete he looked. Yhat Wolf as a combination of all the above would be started before the ballot finished and sometime in the past month since the last update is not surprising in the least. And it's been often said and speculated and predicted, but with Star Fox Zero originally intended to come out in November, a month away from now, from a promotional standpoint Wolf makes the most sense of the three to come first, liking with Shovel Knight whose Amiibo is scheduled IIRC to come out in November sometime around the release of Falco and Mewtwo's.
Bomberman isn't so random a choice as you may think. I see the three ballot choices as a good mix - a veteran, a highly-requested Nintendo newcomer, and a 3rd-party with a good history with Nintendo. Bomberman, as the latter, does a good job of filling that description. Bomberman is one of the most Nintendo-like franchises that aren't owned by Nintendo, and indeed, Hudson was a major Nintendo supporter in times past before they were bought by Konami, with Bomberman their mascot character. While Bomberman hasn't garnered the support of Snake on the forums (for understandable reasons, but also keep in mind that the forums represent a small fraction of the most hardcore fans, and the Western ones at that), he makes more sense from a couple angles. One, he fits better into Smash than Snake. Two, Snake was added because Sakurai and Kojima are friends, so the stuff going on right now between Konami and Kojima over the Metal Gear series definitely does not lend itself to Sakurai or Nintendo negotiating with Konami for Snake's rights again. They definitely could, however, go to them for Bomberman, who besides Simon Belmont and Snake is probably the most recognizable character Konami has the rights too, and also has a huge history with Nintendo (Bomberman 64, IMO, is one of the best games ever on Nintendo consoles). Three, his moveset lends itself well to Smash. I personally don't see the Snake moveset comment as an issue, because it was said that only some attacks were taken from Snake, and it never specified which (for all we know it could be all A attacks and not specials at all). Rest assured that Bomberman wouldn't be Snake in a different proportioned body. After all, he best character to take Snakes moveset in its entirety, with some small tweaks, is Sami from Advance Wars.
I can see some people getting to this point already getting hung up on King K. Rool from the standpoint that the leak said that he looks like his Mii costume, but the leaker not knowing which came first. 'Obviously,' they may think, 'the third slot belongs to K. Rool because he already has a basis to work from because of the costume', while others probably think along the lines of: 'Well he's popular and obviously he's been in production for awhile because the Mii costume was based from his model!' But hold your horses! Being a newcomer, K. Rool would understandably take longer than Wolf to make, and this is a good thing as it means he'll be unique and not exactly cloned from anybody else necessarily. He also, like Bomberman, doesn't have the benefit of a new game on his side (that's been announced anyways; the biggest part of the leak actually is the non-Smash info, namely, that there's a new Donkey Kong game in the works and it's implied feature K. Rool, hence part of why he's being included to promote the DK series) like Wolf does, nor does he have a game in his series in general releasing the near future like Wolf does/did. If the order of the three characters is any actual indication, he'd be the last of the three to release if not at the same time as Bomberman and/or Wolf.
Shovel Knight, of course, has been beaten to death. With a shovel. The shenanigans with Yacht Club Games' Twitter feed and then going silent and awkwardly reshuffling their plans amidst the lack of his reveal on the release of the patch is actually fairly interesting, and alongside all the evidence that's come up in support of his inclusion alongside Tama's original rumor makes him fairly likely, with a release either this month or in November coinciding with the Amiibo release.
Of course, I said five characters, and I've only talked about four. We still have one more pre-ballot character to consider. That character is Professor Layton. We've already had a rumor about his inclusion with the whole VA thing (for those not in the loop, someone asked Layton's VA on Twitter about his IMDB being updated anonymously to say he voiced Layton in Smash. He replied no, but about a month later randomly changes his mind to maybe, reflecting on it and considering that he did some extra sound bytes like growls, grunts, and yells during a recording session for another project that may actually have been for Smash. He was unsure of what they were meant to be used for and that's as far as I've heard), and for his VA to potentially record voiceover work for him means that not only is he pre-ballot as that story played out in August, possibly even July (I can't remember for sure); but he's also very far along in the design and implementing process, as voiceover work is usually one of the last things to be done while working on a character IIRC, albeit that he recorded the lines conveniently during another session. We've had VA's give away voicing characters in Smash before (Shulk's VA, for example), so it isn't too unbelievable a thought.
Now, that leaves five characters, but wait! We can't have five characters in a character bundle when the first and only one we've gotten has four! We can't have two and three characters in two separate bundles either for the same reason! This is definitely only my own personal speculation and based on nothing but the four characters to a bundle, but if we have five characters, then that means that one character gets left out of the bundle. It would stand to reason, then, that there would need to be at least three more characters to completely a third bundle. As for who those characters are, I cannot say, though the four obvious candidates by popularity are Isaac, Dixie Kong, the Inklings and Bandana Dee, with Toad, Impa, Chibi-Robo and another 3rd-party being less-likely choices. To see 12 DLC fighters would be awesome, and while I don't exactly put stock in the idea as reality, my ideal final number is 16 (48+16=64, DLC=1/4 of the roster, 64 is the highest number of entrants in a tourney, meaning every non-Mii character can be represented without leaving anyone out or doubling up, etc.) but I'll take whatever we get, and even the five we'd be getting is
pretty awesome top of the four we already have, on top of the base roster!
And as far as the stages go, so don't have an explanation for Tikibuzz. It obviously ties into DK/K. Rool potentially but could also
mean that a DK stage is being ported too. The slot above Mario Maker was in the files since Mewtwo, but was only renamed in the past month. We can assume that every 3rd-party is getting their own stage, so Shovel Knight take the two new slots while the old one was probably meant for Pirate Ship but may now be for Jungle Hijinx? I don't know, and it doesn't account for Wolf's SFZero stage. Though with Wolf being a ballot character and recently started within the last month, it stands to reason that they haven't started work on his stage in any meaningful capacity yet. With potentially three stages being worked on right now plus Bomberman's later on, I can understand why.
So, I think that should be it! I hope this was thought provoking and can garner up some nice, healthy debates. However, I really don't want to see any debate centered on "these rumors are fake, so your entire post is automatically wrong". They have not been proven fake - Shovel Knight has been going strong for a while and has actually grown more likely as time has gone by, while the 4chan rumor not only survived the latest wave of DLC, something 99.9% of leaks don't as someone put it earlier now the thread, but it actually got a prediction correct, albeit a possibly obvious one, which is why we're giving it any thought instead of dismissing it outright like every other 4chan "leak", sans the ESRB leak. So, pleas approach this with an open mind, and even if you don't believe it - which is completely within your rights to do - please be rational and entertain the thought rather than make your rebuttal centered around dismissing it.