Good choice. CTWM and Sawfish are two of the best and more configurable window managers there are.

Unfortunately I had to give up on both years ago when they got unmaintained on Debian and not even compiling them from source would make them avoid visual glitches that made them unusable (especially after running Firefox (!)).

Now I use KDE (also quite configurable, at least keyboard-wise) and my life is a little simpler in some ways and my experience a little more annoying in others.

try out fvwm2, it is pretty awesome!