This is a real annoyance of mine. None of the real nice mechanical keyboards are available in a fullsize layout. A numpad is NOT negotiable for me...several creative apps I regularly use use the numpad for control (and no, the regular number row keys ARE NOT mapped to the same commands).
Buy a separate numpad and put it to the left of your keyboard. It provides a more ergonomic position for your mouse and allows you to use the numpad and the mouse simultaneously. Keeping the numpad on the right is a relic from the days before mice and is a huge ergonomic error.
Thats...not quite a meant by high end. I mean stuff like a bespoke PCB so you can change all the switches out, an aluminum case... one of those $500+ custom jobs that /r/mechanicalkeyboards likes to drool over.
Full size are rarer and more expensive. There might be some other options.
Honestly the GMMK full size is pretty nice and you can pick whatever switch you want. It doesn't have a custom case like the one I linked above, but its aluminum and you can customize everything else. Some people have even dissassembled the case and painted it.
I have no personal experience whatsoever with these, but the Corsair keyboards have a very bad reputation among mechanical keyboard enthusiasts. Allegedly the keycaps are made of low quality ABS plastic, and because some of the keys are non-standard size, you can’t easily find replacement keycaps.
Among mainstream brands, Ducky and CoolerMaster are supposed to be much better (I have no experience with these either).
I have a CoolerMaster Masterkey Pro L with Cherry MX Browns - Its a nice keyboard, well built and not too showy. I got it for the office and I didn't want something that was very 'gamer-ey'. Only criticism is that the Cherry Browns are nowehere near as nice as the Gateron Browns I have in another keyboard (although I suppose you can't put this on CM). Oh, and maybe the ABS keycaps, they aren't great and the PBT Keycap 'upgrade kit' that CM sell isn't really a direct replacement. I'll probably pick up a separate PBT Double-shot set, but that's optional. I have recommended the CM Masterkeys Pro L to a bunch of people. I had a Corsair K70 (trampstamp edition) a few years ago, and the quality was good but the non-standard bottom row got on my nerves because it severely limited keycap replacement options.
Ducky One 2 user here: it is fantastic for the price. The aluminium case is solid, heavy and beautifully shaped and coated. Switches are perfect to me. Stock keycaps are very good though maybe not the best.
I like it so much I'm using it with both my computers with keyboard/mouse sharing software.
