Mine would have to be the veiltails, doubetails, deltas, and half-suns and half-moons.
Combtails are nice, too. ^^;
The only male Betta (Mr. Wimpy Fish) that I have EVER had is a veiltail.... And he's, like, REALLY pretty, so, thens, he's my favourite.
I think my aggressive female Betta fish (Metamorphix) might be a slightly-combtailed fish, although I'm not so sure, myself.
^^;
And, of my late females:
Royal was a combtail (sort of), and Tropica was a crowntail.
And, of my living females:
Aqua looks *very* much like she *may* be a spadetail, Taffy I'm not sure but she may be one, too (but she has fin-rot so I don't know), and Queenie is a (sort-of) combtail! ^^;
And that's my girls for you!