Lots of places to trim the budget on this guy.
1) Swap 3770K for 3570K unless you are going to be doing multimedia creation.
2) Swap the RAM you have selected for
this, or
this.
3) Get a better case. If you want something white, look at the Define R4, CoolerMaster Stryker, NZXT Switch 810, and BitFenix Shinobi XL. The Fractal Arc Midi, Lian Li PC-7HX, HAF XM, and Silverstone TJ04 are all good options too.
4) Swap PSU for
this if you get a second 670, or
this if you are going to stick with a single 670.
About your requirements, no one knows for sure what those beta titles will require once optimized. Can't give you any guarantees.
UE3 games will require you to clock your processor to the 4.3-4.5 region in order to maintain a good framerate. It's heavily processor bound. The most out there next to Starcraft 2.
Only SLI if you are willing to deal with random patches and workarounds to get it going on newly released titles.
Watercooling is fun, but a very expensive hobby ($500 budget to be safe) and it's only really worth it for people who like to constantly tinker with hardware.
For a heatsink, it's hard to beat the Hyper 212 or Xigmatek Gaia.