No Interest: Succubi, Gnomes - The former feels shoehorned in (through no fault of their maker, I just feel a "demon" race is a poor concept to add to the setting Masterowrk has sort of woven for itself away from vanilla and I'm not totally sure why I think that since it looks like a very well made race,) and I greatly dislike machinery beyond using it for life-sustaining functions which makes gnomes pointless for me to use unless I want someone with guns besides humans/equally puny to fight when playing as orcs/warlocks or kobolds.
Haven't given a try, really should and been meaning to: Humans - I still feel it's not fair to restrict selling excess crap to them when dwarves had the buy/sell thing first
Play rarely: Kobolds, Hermit - Kobolds genuinely amuse me, but old age seems like a far greater threat than invaders (worst comes to worst an emergency dirt warren can be sealed up after all,) and hermits for when I feel like just doing something different and working with few units. Bob still needs to be made zombie friendly unless that's changed at all recently.
Play Occasionally: Orcs, Warlocks - Orcs fit my playstyle best being combat-oriented and generally much tougher customers short of undead and megabeasts than anyone else. Warlocks I have really, really wanted to do a story fort for I like them so much, but I just have too many ongoing things as it is; I love their concept and they fit with Masterwork's more high fantasy theme extremely well, but lack of migrants by design makes it difficult for me to really get anything done without constantly worrying about skeletons derping up and going unpowered.
Play Frequently: Dwarves obviously - I still have yet to truly play them to late game; haven't made much use of runes, little to no use of the inventor's lil copycat ways to make more khopeshes from the ones the drow bring much as I've meant to, never touched golem forging (because it east dwarves,) volcanism, hardly scratched alchemy since I typically have little use for it by sheer dumb luck, really there's tons about just the good ol' dorf I haven't even touched.