As written, this is a tough one to answer. I'm well served in most genres bar a few, and I probably wouldn't want to see new entries from the people who made the old ones. For instance, I miss stealth games and Splinter Cell, but I wouldn't want Ubisoft to make it. I would love to see a new Metal Arms, but Blizzard (and now also Microsoft) owns that one. I miss racing games like Burnout and F-Zero, but I wouldn't trust EA or Nintendo to make a successor that makes me happy. So really, I think I want new stuff that's more of a spiritual successor type of deal.
I've been wanting a new, proper Splinter Cell for years. Michael Ironside is cancer free now and still alive for a couple more years (hopefully). I dream of Sam Fischer getting a final send-off with the correct voice actor. "One final job" with him old and grey. But yeah, Ubisoft wouldn't make it right, sadly.