I'm about halfway through my first playthrough on hard and I've never tried anyone besides Lloyd successfully. I gave Colette, Kratos, and Genis a shot earlier in the game but I seemed to do poorly. I've got all but Kratos and whatever the last characters name is.
I'm getting this for the PS3 but I've been watching someone on YouTube do a playthrough of it but I would play as Lloyd, Krotos, Sheena or the Mystery Axe Girl (Not her real name BTW) just being sure not to spoil anything plot related.
Nintendo Network ID:Zack1997 3DS FC:0301-9783-2635 Playing:MK8, Xenoblade Chronicles and One Piece: Unlimited World Red Waiting for SSB4 and Pokemon Omega Ruby
Personally, when I started playing this, I played as Genis frequently. However, this was largely because it was my friend's game and he enjoyed playing Lloyd, so i would take Genis. On my own, I find Genis a very difficult character to use as the other NPCs don't seem to like giving you any sort of help by distracting an enemy.
My first run I switched to "Ax Girl" when I got her, and now that I'm replaying on the PS3 version I'm wondering how I ever did it X_X Lloyd is just so much like the other main characters in the Tales series when it comes to fighting and now that I've played the others his move set just feels like home.