Hi BullRage. Welcome to Geekhack.
Geekhack would be the place for custom boards, that's for sure.
You must have done some research if you've come to all of these conclusions without trying anything other than Cherry. Linears are usually a pretty good bet for gaming if you ask me, but maybe that's just because I've used MX reds for that purpose since I dumped rubber domes years ago.
I'm no fan of MX (or clone) tactiles myself, but if you like clickies at all, you'll love both jades and navies. The navies are pretty stiff though, especially for someone used to the lighter MX switches like brown, red, and blue. Even jades are going to be a little jarring by comparison. Jades are wonderfully bassy for a clicky switch though. If either of those seem too heavy, at least to start, box pinks are a great compromise too.
I think 75% is a great compromise layout. I don't think I really need anything that big myself, but I couldn't go any smaller than a 60% with dedicated arrow keys either, and seem to use full-sized boards more than anything else anyway.
Personally, I wish Noctua made some more fans that weren't different shades of brown or cream myself. I'm sure they fit some builds great, but I find myself trying to hide them, if I bother to get them at all. I stuffed some in some version 1.0 original Xbox consoles for a cooling upgrades, since they're hiding under the optical drive anyway. That IC sounds interesting though, although I don't have a huge interest in caps myself. I wish you luck in your endeavour.