Ubuntu default (desktop) is a huge iceberg with a lot of included stuff. I learned to avoid the 'main' disto file and go for the minimal-install a while ago (which is embarrassing for a former Slackware person? - just used to the smoothness of Ubuntu and Debian base); I use GNOME as the WM on Ubuntu.

tl;dr Base Ubuntu install strapped to bare-bones from the start, then adding bits as necessary. Bloat hopefully doesn't exist in 32MB.