Mine would be.
GTA san andreas freedom.
GTA V/gta 4 and red dead redemption phyysics.
GTA V's map but without the stupid big useless mountains.
driver parrelel lines full car customization freedom. including customizing police cars and tanks etc.
No online. If there's online, something simple like how gta 4 was.
Real life cars with full crash phycsics. Fake cars are cool too.
Absopultley no alians or zombies or any of that crap. Keep that stuff for half-life etc etc.
san andreas cheats.
No stupid trophies or acheivments.
Red dead redemption graghics.