Lucas is a great counterpick against Wolf. I don't know why, I'm sure there's a reason, but I don't know it. My brother isn't very good, but when he picks Lucas I have a tough time beating him. When my friend uses his Lucario against my Wolf, it's usually about 50/50 for winning. I haven't had too much trouble against Marth or Ike, just range camp them with short hop blasters and then only melee when they come in for the kill.
rm88, for your peach, try to range camp with turnips as much as possible while avoiding as many blaster shots as possible. Wolf has a great range camp, but he also has killer melee attacks, so try not to be hit by them if you can. I don't know all too much about Peach's priority in this game. I mained her in Melee, but they gave her a super nerf, so I moved on *cry*