I like the personalities of angels. However, I have a milletseed (lemon) butterflyfish with a confident, bold personality and he's really cool. Visible and fun to watch, similar to the angels.
Otherwise, I think some of the little perching fish are interesting - like the little gobies, blennies, dragonettes, and my geometric pygmy hawk.
Had a pygmy wrasse which was just a very different attitude - cruising along through the rocks with no care in the world about any of the other fish. Need to find another of those dudes.
Dottybacks / basslets also have inquisitive personalities. I like how they watch things and seem to be really thinking. These guys are also a lot of fun if you have a laser pointer...