Young Link is also a lot better in 1.0 (and even 1.1).
I really don't see why lower tier players can't play on 1.0 if they request it. If their opponent refuses, it kinda sucks that their character has to be at even more of a disadvantage.
1.0 actually doesn't affect Pikachu at all, but it does affect (in a bad way) Young Link (pretty heavily imo), Bowser, Link, and any character that has multi-hit moves that can do less than 1% damage including Zelda (especially), Samus, Mewtwo, Peach, Mario, and possibly a few others.
I'll say this now, yes I'm planning on playing YL seriously in tournament (possibly at this tournament, we'll see if I feel confident enough with him by then). But I will refuse to play him if it is not on 1.0