You do have to remember, Skylake might be coming August, but those are not desktop versions or oc versions. We have yet to have Broadwell desktop cpus.
i use a power supply tester and leave the pump running at 12v for 5 or so hours and see if there are any leaks. Psu is elevated higher than the Aio ofc.
check again . the h100i is really loud compared to the Cryorig R1 and Noctua NHD15's and in most cases, the air cooler beats or matches the clc while being quieter.
It seems like it would. The arc mini will support the 360 with removal of the ODD cage. You might wanna take a look at this link:
http://linustechtips.com/main/topic/98498-water-cooling-my-arc-midi-r2/
just try and push the clock up higher by say +5 -10 Mhz everytime and stress test it. If there is a crash then go ahead and tune it back to the last stable OC. Remember that every card is different so OCing will be better for some.