A good title matters. For me, it's very important with my own writing. When I have the right title, things start to fall into place. One way, and you have to check with each prof, because we don't all agree about this, but I quite like titles with questions in them. Because that immediately sets you up on your mission. Right, you might want to distinguish between the working title and the title you hand in, depending on how your prof feels about question marks in titles. For me, I would welcome it. As long as you have a colon in your title, I think you're okay.