Welcome to Geekhack!
Congratulations on making the first step. Now there are only another thousand steps or so before you settle on a few keyboard, just half a dozen or so, that you really like. There are so many keyboards, switches and keycaps that even putting together ready-made bits produces a huge array of possibilities. After that you can build your own keyboard, and the sky's the limit!
Is there anything in particular you don't like about the FC750?