I find you remarks about the UI very interesting. While I prefer Sailfish (for other reasons), I think Ubuntu did a much better job on the UI. Sailfish ist just too restricted and simple for me. Interesting to read other opinions.
I found that for me, the userbase (or community-support) that Nokias Maemo products enjoyed were just enough. It shouldn't be less, but it was OK.
"write once, run on both"