Overrated-plecos for tanks with algue. All common livebearers.
I think bettas get the credit they desirve. They make a wonderful choice for people that are just diping their feet into ''water''. The people that want something more then average can get the lovely halfmoons, clowntails, double tails, and such. To me, even the ugliest betta still looks prettier then the ugliest fish in any other species. I don't know what you mean about them being boring. Some of mine are very active. The ones that aren't as active are still very nice to look at, they swim up to see me every time I come into the room, and I almost have them hand fed. I point to one of my betta's food when I put it in and he will swim to where ever I point. He knows my finger hovering over the water means food is there. He's my favorite. I have 7 of them at the moment and I'll be getting atleast 2 more soon.
Another one that getsthe credit it desirves are Midas and Red Devils. Very aggressive and lots of personality.
Underrated-Dragon or Violet gobies. Actually now that I think about it, all gobies. Four-lined pims, and convicts.