1920x1080 is pretty standard to game with, and you can always bump up later if you find its not enough. You should be just fine with that for now. I would definitely use the 2500k build. Haven't started to OC mine yet, but overall a FAR superior chip. Bulldozer is only rumored to be able to go toe to toe with it. I haven't seen anything saying it could beat it. SB is definitely the way to go right now.
750W while excessive is not necessarily bad. It will allow you plenty of room to move up later for a new card (which may require more power) or any additional items you may add. It will also allow your PSU to run cool. I have been a big fan of giving PLENTY of leeway for the PSU so it doesn't have to strain (again just a personal preference). If you're concerned about budget however cutting down wattage would definitely be a way to cut back on $$ a little bit. And also check out the True/Tested PS sticky
http://www.overclockers.com/forums/showthread.php?t=589708 . It's very straight forward and as long as you pick something on that list you probably won't go wrong. I also would like to suggest modular. Not needed what so ever. But if you have the extra money its a VERY nice perk. It does reduce heat somewhat, but mostly its just SO much easier to work with, and MUCH more aesthetically pleasing (especially with the HUGE window on that NZXT case!).
As for additional items, those are COMPLETELY up to you. Obviously at least one optical drive (BlueRay or DVD). It largely depends on the functionality and aesthetics you desire from your computer. Unless you have a HUGE problem with noise or want to TRULY push your system I don't see too much of a reason for a fan controller. But if you want it and have the money, it certainly isn't a bad thing. Temp monitoring is done through software, most of which is free. I personally wouldn't dump any money in to it. Personally I have 6x5.25" bays. Only three are used (2 for DVD Burners and 1 for USB 3.0). The other three are empty, and until I begin my Water Cooling will stay that way. But I prefer a very clean uncluttered look, so I don't fill them.
Unless you know for sure the fans that come with your case and heat sink won't cut it (be it sound, or CFM, or even LED color) I would run it up and see if its enough. If you find anything lacking or just want to change it they're easy to research and find later on.
Stick with the SSD AND get an HDD for storage. Just a perk for load times, but I could NEVER go back. Instead of the 2x6850 I would recommend one 6950 (get a reference 2GB model and unlock it to a 6970). I believe it'd be PLENTY of performance for you, including somewhat future proofing (esp at the above res), run a little cooler AND be cheaper.
My last recommendation: It doesn't seem as though you've thought about exactly what you want. Take some time and figure that out. Everyone here can throw out recommendations all day. But if you give us more specifics we can tailor those recommendations toward helping you get the most for what you want. Take in to consideration, budget, performance needs (i.e. gaming, video editing, whatever it may be), looks, over clocking or stock, etc. You can't give us too much information. If we don't need it we'll skip over it. In the end you have to be happy with the build, not us.
