I think you're focusing too much on the company of origin and the idea of getting a new franchise and not enough on the popularity of the character/franchise itself.
Would someone from Devil May Cry, Tales, or Ace Attorney be exciting. Depends on who you are, but yes, many people would likely agree that those who be good additions. There's also a good chance they'd attract a few people who don't already own a Switch. That being said, exactly how big are these franchises? Are the fanbases large enough to make a worthwhile impact on sales? Many of Nintendo's franchises, regardless of whether or not they're already in Smash, have a much larger fanbase than the ones's you listed. Even if you remove the people who don't care about getting another character from an already represented series, the sheer number of casuals who can recognize the character would, at worst, make them even with the people excited for Phoenix Wright or Lloyd.
Again, it's circumstantial. How popular and iconic the franchise is plays a huge part in how well a character from said franchise would be received. As hard as it is for people to accept, a Minecraft, Fortnite, or second Sonic character would likely find more success than most of the other options you listed. That's because very few people outside SmashBoards genuinely care about which company the character originated from and whether or not they're new. They're more concerned about getting characters they like and recognize.
I think you’re missing what i’m saying.
Sure, Nintendo has series that are arguably more popular than series like Devil May Cry. However, the fact of the matter is that it’s highly likely hat fans of Pokémon, Mario, or Zelda that own Smash and a Switch would
already buy the Fighter Pass, or at least buy it on merit of being a Smash fan and would buy anything in the first place. I am of the latter.
The harder sell, the one that provides bigger gains, is to reach out to gamers that not only will have interest in a challenger pack that has Dante, or Leon, or Heihachi, but enough interest to get a Switch, Smash, play other first party games, and commit more to the console. This would be a fan that wouldn’t have committed otherwise, whereas in most cases, the Pokémon or Fire Emblem fan would have bought the pass regardless, and was already
going to get those other games.
Catering to fans of unrepresented series not only marks potential for a new Switch owner, but a new Smash fan.
I’m really not focused on the company. Resident Evil, for example, is the only remaining Top 10 Japanese series in lifetime sales, reaching nearly $100 million. That outranks
several Nintendo series, and provides an entirely new series, an entirely new genre, new music, new stage, and brings a new fanbase to Smash. Pokémon and Fire Emblem,
regardless of their series sales, can’t do that.
By no means do I think either would be
bad. But they don’t expand the crossover, which is what this game is striving to be. I don’t see any reason for the game to stop expanding the crossover by series with Banjo when they have picks that.
Plus, with an entirely new Spirit board, anything outside of Pokémon or Fire Emblem seems unlikely.
Well there's your first problem. Assuming that the 3 characters have to be "topped". Being E3, the two shown off could have been there most hype worthy announcements given the audience for that. And last time I checked, Smash never ends with a "big-bang". Wasn't the case for Brawl, Smash 4, 4's DLC, and Ultimate's base roster.
It doesn't have to be a case of that. A 1st party in this case would be leveraging their audience for Ultimate to check out whatever new game or series they want to promote. If you want a series to succeed, exposing it to an audience like Ultimate's is a sure-fire way to succeed.
Which 1st parties, at this point, would they push? The only 3 that seem reasonable are Pokémon, Fire Emblem, and Astral Chain, but only one of them would be entirely new/need the push.
Adding a 3rd party not only gives the incentive for fans of those series to get a Switch, but it also creates potential for that series to succeed on Nintendo platforms, something that Nintendo has struggled with for over a decade.
I don’t buy this idea that the Fighter Pass would dip in quality just to appease Nintendo fans. I’d say most folks have come to like Joker, and were ecstatic about Banjo.
If Spirits are disconfirmations (which, information suggests that might be the case) and upgrades don’t happen (which, is likely) the amount of 1st party properties for Smash drops
substantially. Yes, it’s based on speculation. However, so is the idea that spirits aren’t disconfirmations.
Frankly I don’t even care if we get two 1st parties. I simply don’t expect it, and I feel that adding 3rd parties heightens the quality of the crossover.
Yes, it’s an opinion. But I think you’d find there are plenty of people who think it’s likely and makes sense. That doesn’t mean folks wanting first parties are wrong. I would simply say that, if you ask me, chances are that it will be an entirely 3rd party pass.