What initially turned me off about DF? Labor designations. Sort through your list of dwarves, give each one some labors, ok, fine.
Now a job needs doing, ok... if there's an idler, he gets it, otherwise, maybe just at random.
That'll get jobs done, but it leads to constantly messing around with labors, which is terribly inefficient.
Then I got dwarf therapist. Thank goodness for dwarf therapist.
So now what turns me off? The knowledge that even with therapist, with every migrant wave after the first couple small ones, I'm gonna be spending 5-10 minutes (at least) re-organizing my labor force.
Recommendation: Please, for the love of Armok, give me smaller migrant waves! (like 2-8 migrants a season) I want to be happy to have more dwarves to work with, not annoyed because I have to spend more time paused doing labor re-assignment surgery.
And I'm the type who typically enjoys micromanaging things to that level. The typical newbie is probably much more annoyed than I am. And this is all with a 3rd party tool that is a million times better than the in game method of assigning labors.
Also, the fact that the game pauses every time I do anything. Can that be an option? Maybe I don't want to pause while I designate the next branch to mine.
Aside from that, lack of challenge after the initial rough start, and of course, FPS death, but I don't think there's a simple answer to that.