Hmm, I am a noob and all but I thought about melee infantry only being able to walk up to enemies to kill them, even at similar speed to ranged infantry. From my experience some melee units seem to have difficulty chasing down lone rams, which seems weird. I think infantry should be able to break into a run when attacking units within a certain distance. This would mean you would need to protect your ranged infantry from melee units and rams could be more easily stopped. I think the run speed for infantry should be made up their current run speed unless it needs balancing.