As discussed with Flameeyes on IRC: here's a patch for changing media-sound/alsa-tools-1.0.9-r1 from having IUSE="X" to having IUSE="fltk gtk". This patch also moves the configuration of the $ALSA_TOOLS variable from global scope to pkg_setup().
Created attachment 71804 [details, diff] Diff against alsa-tools-1.0.9-r1.ebuild
Oh, forgot to mention that the patch also removes the --with-kernel argument to configure since it is no longer needed (according to grep).
Committed in CVS.