I would really like to see a new Lost Vikings game as I liked the ones on the SNES and the PC.
They were a combination of puzzle/platform games which puzzles could be tricky but were not fiendish difficult (though I never finished the SNES version so I am not sure how much that holds)
I especially liked Lost Vikings 2 with all those voice actors (can't recall their names)
Another game I would like to see a sequel to is the Boktai series on the Gameboy Advance.
They are your typical Japanese 'fight against vampires and monsters' thing but I really liked the mix of Spaghetti Western meets Castelvania atmosphere .
There was a DS game but I did not like that game as much as I did the original three games, especially part 3.
A new Metal Gear game would also be nice, but not a Metal Gear Solid game.
I am more thinking about Metal Gear 2 Solid Snake, and Metal Gear Ghost Babel (Metal Gear Solid on the GBC here in the West) with its overhead action and focus on gameplay rather than cutscenes.
I would prefer if it would take place in an alternate universe than the MGS one, either another one taking place after MG2 SS, or continuing the Ghost Babel universe.
No more emphasis on nano machines, and while secret organizations like spy agencies are okay, no more the Iluminati like Patriots or Philosophers, I am sick of them.
Another Strike Commander game would also be cool as I really like the alternative timeline portrayed in that franchise; the collapse of the majority of states and the rise of mercenary squadrons.
It would be cool if you could be a member of the Wildcats again.
For that matter, a new Wing Commander game would also be nice.
And while we are at it, why not a real Privateer 3.
Probably mentioned here before, but a Bioforge 2, that game cries for a sequel.
A proper Monkey Island 3.
Look I love Curse of Monkey Island, but since then the series has been haphazard at best, Escape stunk and tales by Telltale went way overboard with the fantasy and anachronism stuff.
I want Gilbert and his former cronies from Lucasarts to pen a 'final' Monkey Island, something in the style of Monkey Island 1 and 2's 'realistic' style that could serve as an ending for the original 2 games.
After that make as much sequels as you want, I could view them as alternate storyline stuff.
A sequel to Sub Culture, a real sequel unlike Deep Fighter.
I still love Sub Culture, the underwater Elite with the minuscule humanoids and their submarines, and I would like to explore a new seabed full of underwater colonies, caverns, reefs, and 'gigantic' sea life.