There are a lot of great ENBs/photomods out there for 2k13. It all depends on what kind of visuals you prefer.
Like for example, my new settings are a bit bright and colorful.



And my older ones are darker.


Before, I used mlp's ENB with SJ's FXAA injector. It produces images that are dark and less colorful, but they still look great. I haven't tried out others though but judging from screenshots, some of them look pretty good too. Just find one that you like.