Well, I picked "other," as I like the quirky Tamarians from the TNG ep "Darmok." And the Jem'Hadar always intrigued me, a race genetically engineered for war. If you think how sophisticated the Founders would have to be to create a race that matures in days and whose members have cognitive skills built into their DNA, it boggles the mind.
I also liked the focus on the Andorians in ENT. It also helped having Jeffrey Combs portray Shran, and the touch of racism in his hurling the epithet "pink-skin" to Archer and co. was a nice addition to their makeup.
And more Romulans, of course, are always welcome! It's too bad the Romulan Subcommander from the DSN ep "The Search" didn't become a semi-regular, but then Martha Hackett wouldn't have gone on to play the duplicitous Seska on VOY.
Red Ranger