Hi Armchair general.
That wasn't really how we amended this.
Our concern was that if you got a good role in the original rules you could march three moves up to your enemy from outside musket range, fire a volley at close range and potentially destroy a unit before it could fire back. This seemed completely in-realistic.
Moving firing to first rather than last takes this out of the equation. You might get to march three moves up to short range but you are going to get hit with a volley at short range before you are able to fire and then charge in. So the Militia at Cowpens will always get their w 2 shots (one with the closing fire) before beign over run or will have the chance to fire once and retire as happened historically. We have found this works really well.
The other amend is to Brigade morales. We wont always use this. For one night 2 hour games you need a quick result, for an all day game Brigades may need to be more robust. So once a Brigade exceeds 50% of its Battalions destroyed or shaken it takes a morale. It gets a -1 for each unit broken or shaken and then has a simple pass or break using the break tests table (anything but a break is a pass) if it passes it doesn't test again until another unit is broken or shaken, however it operates with a -1 to command rolls for each broken or shaken unit. Again this worked really well.