my current machine has approx 40 gigs on the system partition, and the games volume has 150 gigs installed to it.
Might I suggest you swap that SSD to a samsung 840 pro edition/neutron gtx/etc etc etc. You get the idea... the m500's are good, but I wouldn't necessarily use one for the system/games volume.
If you keep it under control, 240 gigs is enough. Heck, 200 is enough. For now? Games are getting big. Real big.
You could save some on the memory... are you intending to overclock? You could get some decent ddr3/1600 ram instead.
I really like my gtx 780, but the 780ti's are a nice bump up... you might downgrade the ram speed, and trade up to the moderately faster card. You could even downgrade to a 4670k following this route, and the gpu increase would be more than you'd lose to the cpu. (which would only really show up in games that are cpu bound).
Note: General advice, rather than listing suggestion upon suggestion.... the gpu is the single biggest factor of gaming performance... spend money there first, then start spending money on supporting items, like cpu, faster ram, etc.
You could also save on the asetek cooling system, again, if you're not intending to overclock. Those AIO liquid coolers are good, and they generally offer performance equivalent to top-end air coolers, give or take... but they lack sheer capacity for super overclocking... given you're spending money already, consideration towards a 240, 280, 360 /etc unit might be warranted.
If you go with air cooling, as I recently linked another thread, the http://www.newegg.com/Product/Product.aspx?Item=N82E16835103099
will serve you well, and is much cheaper.
Two 760's can be sourced cheaper than the 780/780ti, and will at least match the speed, if you want to deal with. Might consider going with the 4GB variants to give them a little more legroom... 2GB is starting to not be enough anymore.