Need help deciding on PSU and CPU cooler

My thoughts:

1. A R9-290 needs about a 650w psu.
http://www.realhardtechx.com/index_archivos/Page362.htm
If you have any possibility of adding a second 290, you are looking at closer to 1000w.
The R9 cards are power hungry so a 760w psu may not be enough for a second card.
2. The corsair AX series is tier 1 on this list and 760 is plenty for any single graphics card.
https://community.newegg.com/eggxpert/computer_hardware/f/135081/t/45344.aspx?Redirected=true
I don't think anyone will recoup the price premium paid for gold or platinum psu. The main reason for high efficiency is to keep psu fan noise to a minimum. Any tier 2 unit will be good. Seasonic, antec, and xfx are safe picks.

2. I suggest that a GTX970 would be a better card for a top build like yours. It will cost a bit more, like $330. But it will be quieter and perform better. Your 760w psu will be enough if you ever wanted to go to dual cards.
About 17% of newegg reviewers gave that particular R9 a 17% negative ratong of 0 eggs. That tracks closely with th failure rate of R9 cards at 15%
http://www.pugetsystems.com/labs/articles/Video-Card-Failure-Rates-by-Generation-563/
3. Really, I think the evo will be fine for a cooler.
I have become a bit jaded on the subject of haswell cooling for overclocking.
How high you can OC is firstly determined by your luck in the bin lottery.
I had high expectations from the Devil's canyon parts and their better thermals.
I found out that the thermals really do not matter unless, perhaps, you are a competitive overclocker.
Haswell runs quite cool, that is, until you raise the voltage past 1.25v or so.
Once you go past 1.3v, then you really do need very good cooling to keep stress loads under say 85c.
But, the consensus is that voltages higher than 1.30 are not a good thing for 24/7 usage.
I have been unable to find any official Intel recommendation on what is a safe vcore limit.
If you are an enthusiast, you can go higher.
Even if you can handle the heat, how much do you really need that extra multiplier from say 4.4 to 4.6?
My thought is that it is better to use the exotic cooling funds for a quieter and less expensive air cooler.
That said, I might up the cooler budget a bit and look for a noctua or Phanteks cooler with a 140mm fan.
It should be about $65.
4. Love the ssd. You might consider deferring on the hard drive. 240gb will hold a fair number of games, and it is easy to add a hard drive later.