Mike's boards are brilliant....
Definitely.
Some obvious benefits come to mind immediately;
Firstly the silk screened component labels will save time.
Secondly, not having to worry about rewinding the inductor, saves time.
Smart battery options will save CPU boards in the future.
Pinning down that tiny crystal saves.....er, that tiny crystal.
I would probably consider selling a "bare bones" kit that included maybe xtals, connectors, FPGA socket and a few other key, "hard to get" parts like the 22M resistor etc.
Sounds like a brilliant idea.