It's a wonder no-one has said this yet but... I'd take a look at a case with cable management (corsair 200r, Cooler Master HAF 912 Plus, etc...). Also a aftermarket CPU Cooler is not a bad idea, a Cooler Master Hyper 212 Evo is a good cooler for a low price! Those would be 2 general inprovements that'd recommend to anyone no matter what they do with their pc.
I wouldn't drop $50 dollars or more on a case just for cable management.Just grab em all, twist tie them, and tuck them into that area between the optical drive and hard drive.
I was thinking about a cooler but my Cpu runs at about 30 degrees idle ad about 50 on load, I assumed that an after market one would not be that greater performance.