Things I didn't notice mentioned...
Zero Suit Samus: She has three jumps (ground jump, mid-air jump, Down B) and tether recovery. Her aerial kicks and Side B are kill moves, Up B from the ground gives combo ability and is anti-air to guys like Kirby and Pit. Both her neutral B and Down Smash seem to just be there to give her a free Smash/Side B/grab. Uses whip to grab, so she still has a long reach. Best played as a spacing, mid-range character, like Samus in her suit, pretty much.
Ice Climbers: Recovery improved. Nana will now use Side B to try and recover by herself, and their Up B works like a tether recover; whichever climber grabs the ledge while the wire is still out will automatically pull the other climber to the ledge as well.
I pretty much agree with everything else you said, other than Mario (heh, I'm biased as a Mario main, so I won't comment), but I think I might have given slightly different ratings. Don't really want to attempt it so I commend you for doing it. Snake and Sonic are the most extreme and hardest to master, and I'm glad. It means the only tourney videos we'll see of them will be awesome.
Edit: I also disagree with Diddy. Jeez, he sounds like an easy character to play as, without considering his recovery. Also, although his running attack does seem like it may be the best in the game, a lot of other characters have running attacks that suit them perfectly for what they need to do.
