Honestly, my ideal would be just have one assignment:

"You have one semester to impress me with an awesome project. Go at it!"

But the problem is actually grading it.

On the other hand, maybe I don't really need to grade it. Just need to grade it enough so that they actually do the work. But the real point is just to get them to do it. Then, any future employer can look more carefully at the quality of work, and interview them, and see if it's someone they want to work with.