InFamous 2 wasn't exactly marketed for it's mind blowing graphics. It doesn't look that great compared GoW or Uncharted 3, but the gameplay is where it really shines and honestly, the graphics are pretty good so I don't see where you're coming from.
Graphics should be the least important factor when playing open-world/sandbox games. I mean Skyrim graphics are pretty good and a big step up from oblivion but the gameplay, personally, is very boring and monotonous for me. For most games on a massive scale, graphics tend take a hit. I'd rather have shitty graphics and great gameplay/mechanics than vice versa (once again Skyrim being my personal example.)