I agree but I don't know how you solve it without locking out player control after a combat engagement has started. One idea I had a while ago was that instead of allowing the player to control units in combat what you do is have one extremely simple "retreat" option. Either the units are engaged in combat or the units retreat from combat to a safe location. This would eliminate combat micro.

The casual side of the RTS audience that doesn't micro anyway will probably like this while the competitive side that has developed with micro existing will hate it.