Discussion boards are mostly a tire fire; they're mostly useful for dealing with platform problems. They can probably be better when you restrict access to a qualified class but they don't really scale.

>Automatic grading sucks, especially for programming

I'd probably say automatic grading sucks, "even for programming." At least automatic grading can evaluate outputs of non-trivial programs. Programming is one of the few areas where autograding works for non-trivial, not multiple choice, questions.