Master Chief and DOOM Slayer should both get in. Microsoft, at this point, owns a lot of characters/series that are fairly important in some way. Fallout, Warcraft, StarCraft, Diablo, Guitar Hero, Pitfall, Call of Duty, Crash, Spyro, probably more I’m forgetting…
Honestly Smash is kind of muddled with what its purpose began as, and what its marketed as and thought of by fans as now. Like a decade or so ago, people would’ve just considered it ridiculous to have Master Chief (or Cloud, for that matter) even considered as an option. So Banjo’s inclusion more reflects the past thinking than the present. It mildly reminds me of the fandom infighting before both Banjo and Steve got in. If there is another game with a lot of third parties, I’d prefer Master Chief (and possibly a few others) get in in addition to Banjo and Steve, not instead of them, though that may depend more on what the game’s purpose is stated to be. I do kind of like the idea of a Nintendo VS Microsoft title, possibly.
Anyways, the real question is: where is the pinball representation in Smash? And I ain’t talking Waluigi Pinball, either!