The 7600k is on the older side of things right now, he might want to check out the Ryzen 1600 (or upcoming 2600), or the i5 8400.
If he gets an R5 1600 he also saves money on not needing a cooler (a really good one comes stock with it).
The spec-04 isn't great for cable management, and I'd honestly recommend something other than that, but I can understand the appeal, especially at that price point.
He may find himself needing a fair bit more storage capacity than 500GB, but that is dependent on how many games he'll have installed at any given time, etc. Ideally if he wants an SSD he could look at a 250GB ssd and a 500GB HDD.
That power supply is a lot more than he needs, he'd be fine with 500-550W of power.
Other than that, no incompatibilities or problems, just alternatives that might be easier on his wallet and improve performance, etc.