Its going to be a gear thing for you. That combination will probably be as good as any other once you're geared up. 5 locks is possible just like 5 hunters, and you'll probably go just as far as 5 tanks. Its like a mythic+ cap can only go so far, 5 tanks not enough dps and 5 dps die quicker.

I think most people are just leveling teams right now to prepare for BfA. By the time you're geared up the pre-patch will be out. I have started just farming achievements.