I have given serious thought to making my own keyboard essentially from scratch, sourcing keys and switches online and then building my own curved "plank" to mount them on, and soldering my own logic board.
My dream keyboard would have the following features:
1) curved "amphitheatre" key rows
2) double shot ABS demi-conical keycaps with transparent symbols. (appear black except when lit from below)
3) Illuminated keys that are not only switch-able, but dim-able as well. (I plan on PWM and tricolour LEDs so I can chose my own custom colour and intensity)
4) relatively quiet mechanical switches, possibly MX Cherry reds
5) Ctrl, Alt, Meta and Windows keys as well as a double row of Function keys. (I got my computing start using terminals and I miss some of the dedicated keys those keyboards would have) with status lights for each
6) rubberized shaped buttons for the keys commonly found on "media keyboards" (calculator, email, favourites, rev, fwd, play, vol+, vol-)
7) horizontal bar Enter and Backspace keys
8) USB port on the right side for occasional thumb drive uses
9) wireless, with one of those RF charging mats built into the desk to power it, on-board batteries to run it when I remove it from the pad
I have the skills needed to make the board itself, it's the logic board inside I'd need help on. As far as I know, it should be fairly easy to set up some sort of an IC that can map the roughly 150 actual key switches and output the appropriate actual keyboard signals. From there, it should be trivial to tack on the 27.8 MHz transmitter that sends to the USB receiver. I don't have much need to program macros and those few I use can be handled in software on the computer.