Sunshine's defining characteristic was really the expansive parkour abilities that your character got. Many great games since then have really aped that in a positive way (though it is something that people would have done with or without Sunshine): Assassin's Creed and Arkham City come to mind first off. Crackdown also, though few people seem to remember that game lately.
Essentially, what's the point of an open world if your character is not empowered to explore it? Realism is only so much fun, and if i wanted to wander around a city, i could just take a bus downtown.

Monster Hunter: pissing me off since 2010.







