Cloud is difficult to level up. Enemies in random battles adjust their levels to fit the highest level character in your party, wether they actually fight or not. At least, that's how it's been for me so far, and that makes it really difficult to level Cloud up without him dying in one to three hits.

Back on topic now, I still think Rafa and Malak are generally useless. I might use them a little right after I get them, but then I get other, better characters and they just never get used again.