I'm a big fan of Elder Scrolls & Fallout, so what I suggest is a molding
of the two games u have & make a M.S.P.R.P.G.
(Massive Single Player Role Playing Game)
Take all that u have & make a giant free roaming sandbox game w/ ALL
elements of a rpg, exp. leveling, perks, ball leveling.

A midevil realm w/ futuristic 'relics' scarcly spread about.
A main quest,side quests, mini-quests.
Fat chicks to skinny. Collect/harvest mushrooms, weed, etc.
Mix to make potions. Wide variety of weapons.
Start w/ rocks,spears,bows. Then get pistols, shotguns, & machine guns.
It'd be a mix of all you've done so far in 1 amazing package!

If you like this idea throw up ur support & any ideas to help convince
them this is a good idea!