I didn't really get the first post, but for second, town bell isn't that essential now, because half of your workers are professional soldiers, not to mention you have advantage of producing units at your place. For attack move I though something like that in this picture Black dots are unit which had the attack move command, when one or more encounter the enemy they begin to engage the enemy and stopping moving in ordered location, then the checking if all units in the red circle (which has fixed radius, maybe can increase from amount of units) are in, the center of the circle is calculated by center of the green rectangle, which is created by left, right, up, down most unit. Okay maybe this is stupid, but it's one of the views how should this command work.