My main gripe with chromebooks is that they don't have a windows key (KEY_LEFTMETA). As a xmonad user, I have quite a lot of functionality bound to that key and I'm not too sure about moving it over to KEY_LEFTALT (mostly because of conflicts with my Emacs key bindings).
Have you tried overloading the search key (used to be caps lock). This key is roughly useless outside chromeos (and I never used it inside chromeos anyway). I am planning to bind that key to my windows-key when I get home tonight so I can use the keyboard to get at my Unity launcher.
As an aside, I was very impressed how well Unity runs on relatively anaemic hardware. for running a terminal and a web browser it runs great.
That's a reasonable alternative and something that one could get used to. After all, Vim and Emacs people have been rebinding Caps Lock to Esc/Ctrl for a long time. One possible downside is the extra strain that this would put on the pinky.
An alternative that I've been wondering about is key sequences (M x) for WM actions and key chords (M-x) for all other things. This seems possible to do in xmonad (last point in this blog post [1])
