Mass Effect 1. There were bunch of planets were you could loot for various items.
It was big and gave you a feeling of what exploring other planets feel like. The music was appropriate for the environment.
Sure it had bunch of places that were identical but it let you approach a fight however you want: by foot, in a vehicle, far away sniping or close quarters with a shotty. Those were the days of ME1 until Gears Effect 2 replaced it with streamlined gameplay and no sense of exploration or RPG elements at whatsoever.
Here's an image of Mako ( armed with a cannon and a machine gun), which I did a lot of donuts and mountain climbing. Perfect vehicle that was removed from the game because weak sauce gamers couldn't control the vehicle.







