Considering how plain jane and lack of surprises too many of these figures have ended up, my list of "essentials" has drastically scaled back during the last couple of years.
Figures I'm 99% sure I'll buy "knowing" what they'll look like:
Marlena 2.0, possibly other 2.0's
certain more interestingly-executed NA characters
possibly some Filmations like Strong Arm
any original 4H characters
Heads that are too goofy/cartoony a la Clawful/Leech/Spikor could be dealbreakers, but in general those are what I'd be signed up for. And yeah, some that are particularly well done could win me over too. Rio Blast isn't naturally at the top of the pile for me (sorry Noisy!) but guarantee me an awesome head sculpt and I'll happily buy him.
And yeah, I know, I should feel guilted by the MotU fandom for not really wanting to support the more fringe stuff like PoP B-listers and so on. But from my POV it isn't my fault. I just don't think that outside of the Classic MotU characters there are that many solid, unique characters that have stood the test of time. Yes, there are many with potential
to have cool figures made from them, but not without more interpretation and redesign than what is permitted within the confines of MOTUC.
Just my take, no offense to fans of any particular character.