Good spot on the CPU
Like I said, I'm not that familiar with the range of options in professional graphics cards. The Quadro K2000 is from what I can see, essentially a pro version of the GTX 650 card. In the consumer range, that has been replaced and outclassed by the newer GTX 750 range (which you can get for as little as $100). I don't think that change has carried over into the Quadro range yet, but perhaps something is in the pipeline. This kind of illustrates how much more expensive these cards are. It looks like a solid mid range professional GPU choice at the moment though.
There's some reviews of the workstation cards here for further reading:
SSD's have come down significantly in price, and there's quite a lot of competition between brands. Prices of the high end enterprise SSD's are still high, but I think the Samsung Evo's offer a good price to performance ratio. The Cooler Master liquid cooler is remarkably cheap at around the same cost as a large air cooler, but it seems to be well reviewed - http://www.frostytech.com/articleview.cfm?articleid=2744&page=1
The 550w power supply would be easily enough for a single AMD Fire Pro W5000 or Nvidia Quadro K2000 GPU in a PC like that. These aren't especially power hungry cards (easily under 100w maximum power consumption in both cases). The really powerful cards in the workstation class, like the Nvidia Quadro K6000, are uber expensive. If you want to have extra capacity for possible expansion then that's fine of course.
Edited by jonuk76, 06 July 2014 - 06:02 AM.