For a while I was really hoping to see Metal Gear Solid remastered in the MGS V engine since it works so well and looks great. Someone then mentioned the original Metal Gear games and that became my new favorite plan. I never even played those games and would love to see them updated to modern graphics and expanded to fit properly in the insanity of that franchise.
Of course, neither Konami nor Kojima are going to make either of these things happen. I think if anything gets any sort of remaster it will be MGS 3 since they already did some stuff with it for those stupid pachinko machines. Still, I can dream...
The most plausible remaster I'd like to see, however, is We Love Katamari. I loved playing through Katamari Damacy again and the remaster is fantastic (aside from the locked framerate, but that wasn't too bad). I can't see any reason why they wouldn't also do the next game since it's visually and functionally almost identical.