Dr.Mario is just a clone (the most original one out of 3 we have in this game) and is basically Melee Mario (but still didn't deserved). Pokemon has way too many things to choose, but it could have few more newcommers (or at least pokemons like Ivysaur shouldn't have been removed). There wasn't any reasons to cut Lucas other than to give Ness his specials (but then that would make it very easy to make Lucas). Mother just doesn't needs any more representation it had in Brawl, where it was just right (maybe few more enemies in Smash run, but not too much). KI should have been left with only 1 character though. Impa is still not "must have" character, unlike every other LoZ character we have already playable (Toon Link represents games like Oracle of Seasons and Wind Waker, not just Wind Waker Link, so, he is "must have" character too).
I don't have any faith in Sakurai since September.
Ridley MUST be playable, just like Meta Knight. He appeared in all Metroid games except for MP Hunters, MP2 and Metroid 2, he is one of the main bosses in all of them, he is important to the story in Prime 1 (started events of this game), Super Metroid (same thing here) and just Metroid (he is the reason why Samus is Samus). He is also highly requested. If he doesn't needs to be playable, then neither do Ganondorf ("fits role of a boss perfectly"), Meta Knight (fits role of a assist trophy) and maybe even Mewtwo (fits role of a legendary pokemon coming out of master ball). Metroid can't remain with Samus twice as playable characters and without 2nd most important character in Metroid and just an iconic character. Like you can't have Mario without Bowser, Kirby without DDD, Link without Ganondorf, Pokemons without Pikachu (who is just an iconic pokemon that appeared everywhere, not something very important to the franchise like Bowser, Luigi and Mario) and Donkey Kong without Diddy Kong, you can't have Samus without Ridley. Once he is playable, Metroid's character representation will be perfect. Anything more than that will be just extra, even Dark Samus. We just need 2nd Metroid character (ZSS Samus doesn't counts because its still Samus), not 25 more characters (and only 1 other character who isn't Ridley - Dark Samus - is not a complete waste of slot, but still nothing compared to Ridley).
"He doesn't cares for DK" came from the fact that DK has nearly no content in the game despite being a very "large" (don't know which words i should use for this kind of things) franchise. Not even items, stages, assist trophies, characters, smash run enemies, etc.
While he may care about those franchies, he certainly has screwed up priorities for them, especially with KI (too much) and DK (not enough).