My thoughts:
-The Kraken is a good cooler, but $130 for a CPU cooler is pretty steep. If you're going to spend that much, might as well go for a 6-core CPU instead, as the return-on-investment isn't very good. There are a lot of $30-50 coolers that are 95-99% as good. I also don't generally like AIO watercoolers, as pumps don't last forever and tend to be noisier than fans + heatpipes. I'd only recommend one if you're planning to delid.
-Arctic Silver 5 is not among the best thermal compounds today. If you end up going with something like a Noctua cooler instead, the NT-H1 compound included is better than Arctic Silver 5.
-I would consider going with a lower-end video card, considering how we're kinda close to a new generation. I suppose you could sell the 980Ti and upgrade when the new cards come out, though.
-I, personally, haven't used a CD/DVD drive in close to 7 years. I've stopped including them in my builds.
-I don't generally use full-tower cases anymore as I have a personal thing against cases that are unnecessarily large. Your full-tower case will be mostly empty space, and because it has such a large internal volume, you'll need more fans (and thus will have more noise, more cost) to have the same internal air velocity. You can probably fit everything you want in a good midtower, and have the same cooling with fewer fans.
-Ditto the above commends on sound cards. Just a heads up, but the motherboard you've selected has the same op-amp as Creative's Zx soundcard, a headphone amp, and uses Creative's software, making the soundcard largely pointless.
I'd probably shave some of the costs, then probably upgrade the speakers and/or headphones, depending on which you use more.