Without some marketing cool characters like Shulk, Lucario, Wii Fit, every Fire Emblem character, and even the mentioned Ness, Lucas, and Palutena probably wouldn’t have ever made it, and the game would feel weird without those strange marketing characters
I could easily live without these characters, but everyone has their own opinions of course.
I don't think new characters should take all the spotlight for Smash. To me it never made sense to even like a new character that much, especially if they're from a new franchise. Why would you like a char so much that you "just got to know"? I mean sure I can see it for franchises you like, but something completely new? Can a bond to such a character really get created in such a short time? And even if yes, it doesn't really compare to what bonds people already have with long-time existing characters that they loved and supported for all these decades.
I can easily accept newcomers that are popular, have a good reputation and a few games already. Like Pikmin, Splatoon and more.
Third parties are even worse. Things like Shovel Knight make no sense to me. Even if you think the game is fun and good. It's just a weird armor with one game that most people just experienced. Why would you want that in Smash and not something you've liked for years?
I've come to the conclusion that many of these followers of weird characters just bandwagon onto them because they already have a following and support, and somehow they start liking them even more as well through this and start supporting the idea.
The same thing holds true for Takamaru or any weird retro rep, and even for K. Rool partially. Many who might not even be familiar with these characters just support them because they're the "popular trend right now that most people support".
Obviously this is a good thing for K. Rool and I know many supporters like him because of the older DK games where he appeared in, so that at least came from more than having just one game, which might only be released in Japan, that you likely haven't even known or played, but still support that character just because he is liked by other people for whatever reason. I also like the ICs, but forcing a retro rep or even "wtf-character" every time and thinking about how cool that char would be doesn't make sense to me. They just take away from possible other spots that more popular, iconic and memorable characters should have.
Well, like I said that's just how I see it. I know I'm biased against some chars and games, but even if I liked some new ones I could easily take and understand them not joining Smash immediately because of being too recent and not having built a large enough impact/fanbase for itself.
I guess I'm also a little biased because DK is actually a big and popular franchise of Nintendo that got neglacted in Smash for too long while other series got more reps just because Sakurai seems biased (KI, FE and even Kirby a bit (especially in Brawl)). If I had my most wanteds I'd care less about who joins or not since I'd be pretty satisfied with what I have. I guess that's how it must be for many people, and they just want some new interesting chars to join.