Turn-based is a must
Isometric is a must
High resolution 2D would be a big plus but I'd still buy it even if were 3D.
Science Fiction genre would be nice (There aren't a whole lot of Sci-fi RPGs)
Some QA for once
Unfortunately a lot of the things I'd like to see are almost certainly off the table given the constraints of a kickstarter project (Planescape: Torment sequel, resurrection of Van Buren)
Basically as long as it's a turn-based isometric RPG there's a 99% chance I'll kick in money.