correct me if I'm wrong but didn't the success of SF2HD lead to SF4?
No, If I recall, it was due to the noticable success of SF2 Hyper Fighting on XBL as well as massive positive feedback received from the unlockable street fighter costumes in the final Onimusha release on PS2.
SF4 was already in the pipline when HD was announced. The game was mostly made as way to appease the fans while SF4 was still in the works as well as major experiment to see if Capcom U.S.A. was capable of handling a SF game without the aid of any japanese development arm.
Even so, I've resigned that Capcom will never touch this franchise again outside of crossover games - and even if they did, it would end up being some abomination that no one would truly enjoy.
They'd try their damnedest to make Darkstalkers into something that would appeal to a wider audience, and doing so would go completely against what Darkstalkers is about. It would just end up pissing off the hard-core fans of the series while not getting any new fans because all the folks who weren't sold on DS before aren't ever going to be sold on it unless they added Akuma, Dante and Jill to the game.
Yup, couldn't agree more.