Maybe I will settle on what I built as really like it or go as small as I can and put on my desk after all. It is 61cm deep and 137cm wide, 2CM green Brazilian soapstone top, pulled out with 2" wood addition on rear to allow cables to pass through. Pretty decent desk size for an RV and room for big audiophile grade speakers on each side of it(DIY of course)
It really depends on how small you wanna go, or if other considerations are the priority (eg. weight, vertical space etc.).
I suggested the cases mostly based on roughly "equal or smaller in size as the Ridge", but other good options may include:
1. Cases that are rather easy to build in, both with AIO and air cooling:
Meshlicious / Meshroom S (sandwich tower), Meshroom D (classic or sandwich), Sharkoon QB One (classic layout), Mechanic Master C26 and C28 (clones are floating around Amazon lately under various different names; classic layout), NR200(P) (the goat), SAMA IM01 and its various clones
2. Cases which are decent for their regular setup, but need a bit more creativity for larger cooling options:
a) Silverstone Sugo 16 - officially supports only 120 mm AIO / radiators, large air coolers up to 172 mm with SFX PSU, but with a bit of creative effort, one would be able to install a radiator of up to 27 mm in top, and approx 220 mm GPU on the side (see my musings in the Mesh-mATX thread,
roughly starting on the 4th page)
b) Silverstone Sugo SG13 - officially only supports LP coolers (for which this thread originally was meant, hence we should split this topic *hint hint*) and 120 / 140 mm AIO in the front.
But there is the "SFX PSU in the front"-mod, basically moves the PSU to the front, zip ties to the rescue, but I've seen 3d printed PSU brackets, too; that frees the space above the CPU for really large air cooling, but in theory, you might also be able to use a 180 or 200 mm radiator (there is a 200 mm AIO by Alphacool)
Well, thats just stuff from either my research or experience (SG 16, Meshlicious / Meshroom S) ...
BUT at this point, I STRONGLY suggest looking up cases at the SFF PC Master List, which lists a whole plethoria of cases with all dimensions, weight, regular cooling options, initial prices and manufacturer links, and then getting either back here and open a seperate thread for your search, or dig deeper into the interwebs / this forum / r/sffpc + co. for further inforrmation
cu, w0lf.