Interesting article, enjoyed reading it even if I disagree with some parts of it.
The comment regarding why Lucas and Roy are in a different situation from King K. Rool is something that I feel is worth noting. The thing about characters is that once they get into Smash, they are essentially "immortalized" for better or worse. In all but four of the cases (Pichu, Young Link, Dark Pit, and arguably Lucina), this has been for the better. As a result they gain a huge fan base and given how Super Smash Bros. is character-driven, these cuts hurt a lot which is why Sakurai specifically emphasized why he despise cutting veterans. It makes sense that DLC serves as an outlet for Lucas (SQUEEEEE!!!) and Roy fans (like myself
) to get their character back so that veterans without a likely future appearance can still come back providing they don't have any legal or technical complications. They also already have a move set done already to be based off of which helps with cutting development costs. This especially applies to Lucas due to his move set being mostly the same as the past game. However, it's also worth noting that despite the changes that some of Roy's changes are similar, if not the same as that of Marth. Regardless, Lucas and Roy as well as other popular veterans are basically guaranteed money for DLC should they not make the initial roster.
Unfortunately for King K. Rool, he's not a veteran. He doesn't have a "proven" fan base because the moment Sakurai mentions him in a negative light or another DK character get in instead, a lot of the less dedicated supporters will turn on K. Rool (look at what happened to Ridley). Furthermore if he gets in, he will be a fully unique character never seen before (thought to be fair, this also applies to other characters). The move set has to be created from scratch and it has to be developed to where people aren't going to use "lol too similar" as a reason to not buy K. Rool. The opportunity cost of developing K. Rool is higher than that of Lucas and Roy and I am 99% certain that he has yet to be planned for a Smash game.
I still think he's the most likely newcomer for DLC given all he has going for him (and let's face it, he has weak competition outside of
maaaaaayyyyybbbbeee Dixie Kong), but recency is not an issue that can be totally ignored for K. Rool even with the ballot giving his chances a significant boost.