On the first day Borderlands 2 came out, I have been seeking ways to edit and improve the game graphically. The game ran butter smooth with all the graphics maxed out @ 4320x2560 so I wanted more.
One of the problems people notice is the frequent texture loading as you progress through the game. After some research I have found a way to disable or fix this effect.
Non-existing texture memory Fix
http://forums.gearboxsoftware.com/showthread.php?t=148641
I recommend you read pages 1-3, after that it becomes somewhat of a ATI vs NVIDIA flame war. Here they address the NumStreamedMips value
Something else I found is that even though Borderlands 2 uses FXAA, which does a passable job. I found out that you can disable FXAA and use another type of rendering from an open source project called SMAA, which has the same impact as FXAA but looks better. Here are some comparison shots.
Without SMAA
With SMAA
Sources
http://www.neogaf.com/forum/showpost.php?p=42272877&postcount=4640
http://mrhaandi.blogspot.ca/p/injectsmaa.html