Well wether you like design or not varies according to ones taste, personaly i feel he's pretty bland but who am i to impose my taste on somebody else. But personality wise there's nothing there, Ryuma barley has a personality of his own.
He's a weaker (as in less interesting and well rounded) copy of Brook with some minor tweaking.
Dude, have you actually read Oda's WANTED? There is a butt load of personality there.