The simple analysis says that larger blocks = more txns = more fees.
But that seems all wrong, as the fee market from FULL blocks is what is making the miners MUCH more money at the moment..
It really is impossible to analyse. The fee market would be less competitive with larger blocks and transaction fees for them would probably be lower, but the less profitable mining is, the less people mine and therefore it becomes more profitable again - it's self-regulating so any changes won't change the revenue relative to hashrate too significantly.