I just read an article about an interesting comp system the Australians are using.
It uses a credit system that allows you to still take powerful units but limits stacking too many together. Each player starts with 20 credits and using their documents adds up how many credits their units will cost them then subtracts that many credits from their total. The balance is then worth battle points for determining tournament winners. I think that it looks complex but then we play 40k so that shouldn't stop us.