Cheers Aethyr
I was also quite impressed by how long my front line held out. Think I got lucky in that the fighting was happening in the gateway, which is perfect for the side with the magic advantage as all the units are fighting head-on in a 2x2 grid, so no swarming can occur, meaning extra numbers are just evo fodder.
Also think it's usually a good idea to keep units well away from commanders during siege defences. As there is a danger that if you put small groups of units on 'Guard Commander', all that does is give a valid target to the opposing thug fliers set to 'Attack Rear'. So in effect all you are doing is giving them a bee-line to your commanders, which usually ends badly (unless the guards can fight off flying thugs).
Look forward to playing in future games with you, be thee ally or foe
All the Best
Calahan