I would vote for getting the car you like and the seats you like and putting them together. Whatever car you want, search the enthusiast's site for it and/or ask if others have swapped in seats, what they've used, how it's turned out. Then get the car, source the seats, and have a body shop do the work for you. Obviously this isn't probably feasible with heated/cooled/powered seats, but I'm assuming you don't need those features.
Alternately, maybe you go to the biggest used car dealer you can find and just sit in all their seats for an afternoon. See what seats you like, and then of the acceptable seats, research which seat has the best car that goes with it.