Alright, so I wasn't all that impressed by Firebird overall... Until I grabbed a few extensions. Most of these are also available for full Moz, I believe.

Also using the "Orbit Blue" theme, which is a bit of an improvement over the default IMHO.

Now I wonder what kind of extensions I can add to Thunderbird. Wish I could get all of the Inboxes/Trash/Junk in one place like Mac Mail. Basically want any "special" folder to be grouped together in a top level node instead of split out under the servers.