I'd stick with the i7 if it's possible workstation usage, while it costs more initially, it has much better returns over time used than the i5.
My personal favorite mITX tower is the Phanteks Evolv mITX tower, its considerably smaller than the fractal R4 (nice tower, I have an R5) and is plain enough not to be obtrusive in any decor, but nice enough not to be an eyesore. It'll also fit standard ATX psu rather than the SFX needed by the node 202 and has no heat issues, it'll fir the U12S cooler. It's also not that expensive comparatively to most other quality cases.
For the most part, liquid or air makes no discernable difference, they all work the same in their brackets, a h55 is comparative to a hyper212, the h60/hyper212 evo, nh-d15 to H105 etc. It's usually budget that's the main difference. With mITX, the possibility of smaller cpu cooler clearance can demand liquid cooling for high cpu usage /OC situations, but that also is dependent on having a 120/240mm spot for the mount. More than a few mITX don't have 120/240mm other than intake, using 80/92mm exhausts. So it's both case dependent and personal choice at the same time, but liquid can offer benefits air can't in smaller cases.