Black Luster Soldier - Envoy of the Beginning - It's too easy to summon. even at one it tends to be a problem.
Rescue Rabbit - 3/5 best decks in japan can all play this guy. and there are 4 variants of the rescue rabbit deck. The Dino Variant. The Warrior Variant, The Fire Fist Variant and the Evilswarm Variant.
Genex Undine - Makes Atlantean Mermails too fast. if not banned it'll probally limited or semi-limited.
Wind-Up Factory - black whirlwind on crack? no thank you.
Limited:
Thousand Eyes Restrict - Without magical scientist and metamorphosis, this guy isn't really broken, especially at one. other than fusion summoning him properly, the only way to bring him out is insant fusion, and then he'll die during the end phase.
Wind-Up Rabbit: - one of the most unbalanced cards the wind-up deck has. this thing has got to go to one. best thing about limiting this guy is that it doesn't affect their current shock master play. but at the same time it lowers the decks speed.
Molten Conduction Field - It's a laval themed foolish, but it's better because you mill 5, 2 originally, and then 3 more off the effect of on the milled ones.
Semi-Limited:
Icarus Attack - Back to two you go. Harpies are nutty fast, and they have plenty of popping power from their new swarm tactics comboed with their field spell. why let them have 3 icarus attack as well?
thats all i got. Can't think of anything that will affect the meta too greatly.