Here's my stance on things. PROBABLY should've put Ray at a BL for D and E.
Wolf has everything going for him right now, basically.
He's Lucas's situation (planned for melee, Quasi-clone put in for Brawl, and cut for Smash 4 with their special moves spread on characters in their series who are from somewhat niche series with region-heavy series)... with 5 differences.
1) Lucas is in the game.
2) Wolf's series is continuing and Wolf is of course in SF-Zero
3) Wolf was less warmly recieved in Brawl (due to being one of the last characters known, alongside ROB).
4) Lucas being more rooted for Japan may have been a further push than Wolf being... most rooted for NA.
5) Lucas's rights are with.. I belive his name is Itoi. Wolf is owned by Miyamoto.. who we know is a good friend to Sakurai. For Lucas, I'm sure the two had to have some small meeting about the rights transfer. For Wolf? Sakurai just needs to go into speed dial.
"YO, SHIGGY! I'M PUTTING WOLF BACK IN SMASH!"
"Good!"
K. Rool is the biggest pushed newcomer and one of the big stars from Brawl demand. His raw popularity, standing relevance for the series (his trophy and Kremlings in smash run should say enough that Sakurai knows it), and strong demand for Smash and Donkey Kong Country Returns together, I believe, trumps the issue of his lack of recency. And the costume? Not a slight obstacle.
Bandana Dee and Isaac... basically are kinda inverses of eachother. Their western vs eastern placements seem about equal, but swapped, Bandana Dee is about recent push in a major series as the 4th major character and Isaac is the protagonist of a "Dated" series that's stagnant.
Inklings are Borderline B/C because... it's a legitimate question about if Nintendo would hold them. Other than that, I WOULD put them into BL A/B. they're just questionable right now.
Dixie and Paper Mario are some big names... but "side" characters to series that either are overshadowed by either the expansion from main disc or one other major character.
Captain Toad is... just a bit below Dixie and Paper Mario just because he is still more minor, in spite of the lingering demand for a playable Toad.
Krystal, Impa, and Chibi are a case of "There's a fair bit of demand but... meh," effectively.
Wonder Red is E because of the actual success of W101 and middling demand. The others of this rank are because "high demand 3rd parties." Indies are there because their makers have been pushing non-stop for them and seem like tey'd would bend over backwards (legal matters wise) and even send employees to make everything as smooth as possible. Snake is... the highly demanded veteran 3rd party character whose situation hasn't really changed since main disc dlc.