The fn/control/alt/command keys ought to have been changable as well, since they differ from system to system and I think a lot of VIM and emacs fans like to change them.
The ~ key also change when you change locale, so that's quite unfortunate that it is static as well.
Personally, I'm starting to get a bit burnt out by all the early pre-order hardware sales lately, but I'm looking forward to seeing the reviews on this thing when it ships.
Can we get e-ink keys separately? It'd be great to solder-my-own for an ergodox.
I'm also interested in keyboards that can change shape. I like the shape of a TI-83, and I don't really like typing equations into Mathematica and LaTeX. I don't have an plan for this, but I'm interested.
The ~ key also change when you change locale, so that's quite unfortunate that it is static as well.