So here's my latest idea for a relatively practical/cheap keyboard design:
Form Factor: TKL with a TrackPoint, browser forward and back keys next to up arrow, Fn in place of Caps Lock, media controls on and around WASD, quick launch functions on 1-5.
Switch Type: PCB-mounted Cherry MX. I'd like MX Black, personally.
Frame: Black ABS.
Keycaps: Black ABS, lasered, with secondary legends pad-printed on the sides, Noppoo-style.
-"Fake plate"-- well, you see, I like the ease of modifying and maintaining PCB-mount keyboards, but I don't like how exposed the PCB is. So the solution (on the cheap) is a "fake plate" made of plastic: basically, a piece of rigid-ish plastic, with raised portions to cover the sides and tops of the switches (like an Azio Levetron Mech4/5's plate) for increased waterproofing, but without anything that the switches actually clip to. That way, you get liquid/dust/crumb protection for your PCB (and switches, too, which is better than a normal plate, even), but if you open up the keyboard and take off the fake plate, everything is readily accessible.
Sell it for $100 or so, though I suppose you could justify going even higher on the basis that there isn't much out there with a TrackPoint.
Edited to add: I have a whole thread full of theoretical keyboard ideas linked in my profile. Wouldn't say any of them are my "ideal"-- not yet, anyway-- but any feature ideas in them are free for the taking.