I definitely don't try to bash other characters, and I'm sad whenever a fan favorite is deconfirmed--sad for the fans, even if it's a character I personally don't care about. And despite knowing next to nothing about the characters, I like the idea of certain characters, like Isaac and Geno, being in despite having no attachment. The only characters I come close to criticizing due to my bias, is third party characters who's slot would go to Banjo & Kazooie (Brawl and 4 only had two playable third parties each, and one has already been revealed for Ultimate). It's a temptation I have to resist.
However, I do believe for me personally, Banjo & Kazooie are the singular missing piece. Now that most big first party characters are in Smash (King K Rool and Ridley being one of the last bastions of that), we have had Snake, Sonic, Mega Man, Pacman, Cloud--it's hard to imagine a character that could top it. To me, Banjo & Kazooie are in a unique position--third party characters, owned by a competitor, who used to be major first party Nintendo characters, up there with Mario and DK. Had Rare not been bought out, there's no doubt Banjo & Kazooie would make it into Smash. And now that it's possible (however unlikely), it would, for me personally, be Banjo & Kazooie coming back home, where they belong.
That doesn't mean I wouldn't want any other characters (my sig has pretty much the main ones I would like), it's that whether they're in or not doesn't concern me as much as with Banjo. I'd love Crash to make it in DLC, so we can have a fight with Nintendo's mascot, Sega's mascot, (possibly Microsoft's current IP with Banjo), and Sony's former mascot. It's a dream match up too good to resist. I wouldn't consider him missing, though--Banjo, however, to me would be missing as it's where he originally belonged.
Dude I just thought of something… Imagine the rest of newcomers are revealed (meaning Banjo would be our last reveal) and once they all fill the spaces in the artwork… the artwork becomes a puzzle like that picture and crumbles down, then the CGI trailer begins for Banjo… It would be such an amazing segway to his CGI trailer reveal…
Indeed, when I was thinking Banjo & Kazooie could be in, and I recalled back to the E3 Direct with Ridley/Daisy being added (prior to the last Direct), I thought of it like putting in pieces of a puzzle, which reminded me so much of Banjo-Kazooie. It just seems so fitting (pun intended).