I think the only other blob that comes to mind is iphb for libhildondesktop. This was mentioned by someone a few years ago in irc chat. If I remember the sources I'm using at the moment (Mer) are not the same. Think it was something about merging bits with dsme IIRC.
Hildon-desktop, if you are still using libclutter0.8 needs libcail (Clutter Accessibility Implementation Library). Newer versions of clutter seem to have integrated ATK support via cally.
mce I think should be blob free now. It only wants the osso-systemui-...-dev packages for the dbus signals etc. I think we already most if not all of them and the actual modules/UI elements in CSSU. I think you said we had libconic sources somewhere.
BTW, CSSU repo is missing libhildondesktop from what I can see. Source is definately available because Cordia and my repo have it.
After addressing iphb I think I should be able to build hildon-desktop using Maemo userland with no binary blobs. For you, it would depend on what version of clutter you're targetting.
Had to take a week off from coding/project. Way to many hours at work the last few weeks. Worked out I've had 6 days leave so far since January Got some time off later this week but have family plans. End of next week and especially all the week after I should finally have some more free time again.