So I've been doing some thinking and really besides Soul Eater, what does Riku really have over Sora? X-Mas Sora has 7/1 status. Sure he has 3 HP but he can play Tink lvl 0 and 1 and boost that up. Riku can't play lvl one magical friends, Sora can and that takes away the direness of the SS ( search specifc) card that seem to appear in Riku Aggro.
Plus you usually only play Soul Eater once or twice during a game, other than that you hit for one anyway.