Talking about MeeGo here - but to be clear - just the core.

MeeGo was not encouraging to device hackers. It had draconian binary requirements which made it very difficult for tinkerers to get it running on devices they had lying around. One more public example of this was in the SSSE3 requirement for x86, effectively excluding any older AMD hardware, along with quite a bit of older Intel hardware.

Mer is a lot more relaxed about this: there's a stock i486 port which should run on just about anything, and on the ARM side, I believe there's an armv6 port, which also widens the door to a hell of a lot more devices (like the n810).

So that's one aspect of where MeeGo failed: running on everything.

As for CE, its aim is to be a community handset UI, day to day usable. I don't know what your complaints with it are (or were) so I can't really address them, and nor do I think they're quite on-topic in this thread, but I do encourage you to get an SD and try the 1.3 release. Things have come a long way, and we've generally got a lot of good feedback, although there's clear room for improvement, and we're going to work our asses off to make that happen. Pop onto #meego-arm on freenode if you need help trying it on an n900.