Both players create lists that add to a certain point value (I'd recommend 1500+ minimum). Note that all the defender's fortifications and respective upgrades must be paid for in this manner. If, through trial and error, we find that this puts the defense at too much a disadvantage, we would give all fortifications a 15 point reduction in base price.

The game board has the Hammer and Anvil deployment layout. The defender has his/her deployment zone to construct his base in whatever way he/she wishes. Terrain should be denser in the attacker's deployment zone, and terrain pieces become smaller and more sparse towards the base (primarily for fluff, this should give the defender's smaller army a decent killing ground). There should not be ruins in the defender's deployment zone-- just buildings (also fluffier, but subject to change).

Roll off for first turn as normal, but the defender must deploy first (they haven't just arrived to their fortress, you see ) The attacker can steal initiative on a 4+.

In addition to the paid for fortifications and buildings, the defender also has what I will refer to as Objective Buildings. These are critical structures like a comms array, an HQ, an Imperial/Chaotic shrine, etc. that the defender is most trying to protect. So far, I think there should be 2-4 of these Objective Buildings, 1 Medium building and the balance Small.

The game follows normal rules concerning game length. At the end of the game, Victory Points are awarded in the following ways:
+2 points for defense for each Objective Building intact and controlled by the defending army
+1 point for defense for each Objective Building intact but not controlled by either side
0 points for each Objective Building being contested
+1 point for offense for each Objective Building destroyed
+2 points for offense for each Objective Building intact and controlled by the attacking army
First blood and Slay the Warlord are secondary objectives, but we removed Linebreaker as that is likely to give the offense a distinct advantage.

We are considering having d3 standard, 1 VP objectives that can be placed anywhere but the attacker's deployment zone in case games need a little more variation.
The defending team has no reserves except for flyers (Everybody should already be in the base, right? Maybe even scratch flyers). There are no restrictions on offensive reserves.