Here are my thoughts.
If you want a smaller case, go with a Silverstone SG05-450. The Elite 110 ITX will severely limit your graphics card upgrades even more than the SG05 with 450W. It doesn't make sense that it can take ATX PSUs (pics show 700W) but you can't even fit the hardware in there for anywhere near that kind of power draw. Otherwise, if you want to use an ATX PSU, go with the Elite 130. Personally I really like the SG05 and find 450W to be more than sufficient. Heck, in theory you can even run a system with a GeForce Titan using that PSU, though the card won't fit inside the case.
How much are you hoping to overclock? You seem to be putting a lot of effort and money into delidding/lapping, extra fans, AIO liquid cooler and multiple TIMs. For gaming you'd be better off with the bigger case and higher end graphics card than putting more effort into the CPU.
No need for crazy fast memory. I would actually use some Crucial Ballistix Sport 1.35v ultra low profile memory due to the lower voltage and really low profile. Might help in the smaller cases where taller RAM can restrict front-back airflow through the case.
I would rather use a single larger SSD than two small ones in RAID. What makes SSDs so much faster than HDDs is the low latency and high IOPS. Even "slow" SSDs will feel faster than a HDD that may transfer at the same rate due to the latency and IOPS.
The NF-S12A fans may not be suitable for use on radiators. In your ITX case choices, the rad fan will be the only case fan.
Why choose 3770K for the second build? No reason to not go Haswell.
this rig is to last 5+ years
If I were you, I'd spend 60% of the money/effort to get 90% of the performance, and then use the remaining 40% of the money in 2½ years to upgrade to 150% of the performance.
By this I mean going with a Core i5 (arguably near identical gaming/overclocking performance) and not bother with all the extra effort/expense of crazy overclocking. You'd end up saving $300-400, and maybe $500+ if you had gone with graphics card liquid cooling. You'd end up with at least 90% of the in-game performance with the money saved.
In 2½ years, buy a new $500 graphics card that will be at least two generations newer and much faster than a GTX 780.