For my purposes, the current biggest problem with Android is that it's diverging more and more from desktop Linux; the security model is now sufficiently differ

For my purposes, the current biggest problem with Android is that it's diverging more and more from desktop Linux; the security model is now sufficiently different that a Debian userland basically won't run. (selinux errors when doing anything with apt.) I used pchroot for a while, which was magical --- it fakes a superuser chroot in a normal user account --- but there's something about recent Androids it doesn't like and it's stopped working for me. The switch to a Chromebook was partly because of this. Crouton seems at least semi-blessed, although recent Chromebooks with Freon no longer support running X in a new VT. (You instead pass through X to a Chrome tab.)