1. With kaby lake available, buy a i5-7600K and a z270 motherboard instead. It should cost no more and perform better.
2. I cool a I5-6600K with a 4.8 OC with only a noctua nh-u12s. No more is needed.
A scythe kotetsu for $35 will do equally well.
Love the ssd approach.
550-650w is fine.
Agree with a better quality cooler.
Pick a tier 1 or 2 unit from a list such as this:http://www.tomshardware.com/forum/id-2547993/psu-tier-list.html