The tabards in feudal age were limited to specific noble houses or guild members or orders. It will be nice it indeed these will be made by an artist and will remain as a normal texture on the cloth forever and to be restricted to specific members with ranks, in a battle each soldier would fight with his noble/captain, they recognize each other so your group will atack another group of different tabard, in real battle there was confusion also, now you are just seek another tabard owner and is very clear, there is not real system for orders... Having only the real emblem owners wearing tabard will need people also to start being more disciplined and to stay near it's own in order to not do frienly fire.