Hrmm Syndicate...
A modern remake (first person, control a small squad of agents say four total) would be awesome for a dark, techno-punk game.
Especially with modern graphics, AI, in a non-linear environment like Grand Theft Auto III. Being able to do things like scout for healthy folks to grab in a dark alley, nerve stable, and turn into future cyborg agents. To doing assassination missions such as car bombings and straight out gunfights would be great.
Then the various implants and upgrades would be wonderful with the new physics engines. Being able to toss cars and crush people in busy city streets when you have augmented strength, etc.
Then fights between rival corporations and their cyborg agents

Of course such a gritty game would be hated by tons of people:
"OMFG!!! Abducting people! Car bombs!!!111 THINK OF THE CHILDREN AND BABY JESUS!!!111"