Good news from the course developers
I've just encountered this comment from a course developer http://www.duolingo.com/comment/16934404#body-17100366
This is great news! Indeed I got 6 feedback emails in the past week, so things are moving.
At this point though I'm personally over all those mistakes (i.e. no longer care much), and would really like to see a major expansion of the tree, which is about half the size of most trees on Duolingo. Does anyone know anything about that?
Sure, I completely understand where you're coming from!
Just saying from my personal experience: I started the French course in Duolingo with almost no background in French, and can now speak French (but not understand, unfortunately) thanks almost exclusively to Duolingo.
For Ukrainian I have a very strong background (being fluent in Russian), but after completing the tree (and repeating many times, all slots are gold), I can't say I speak any Ukrainian. I can't even say really simple things, like 'what happened here?' or 'where can I throw out the trash?' (just random examples off the top of my head). So it's not really about competition, but teaching the basics of the language. The Ukrainian course is especially important because there are very few good Ukrainian resources on the Internet (as opposed to French), and almost no books on the subject. I even searched for a good physical English–Ukrainian or Russian–Ukrainian dictionary and didn't find one.
I am really rooting for this course and sincerely hope that you can expand the tree in a reasonable amount of time.