Battlefield positioning observations
 

Now that I have the battlefield grid turned on ('g' key for overlay on terrain, 'w' key for white grid on black background with no terrain graphics), I can see that it is 28 squares wide by 58 long. If you leave units in the default "center" of your side, with range=25 spells you cannot reach units at the default "center" of the enemy's side, which is 29 units away. And the AI tends to place its units nearer to the rear than to the front, from what I've seen. Also, from the center of your side, you cannot use a range=40 spell to hit units at the far back of the enemy position, which is roughly 43-44 away.

So you need to move casters closer to the front than the default start spot, or use range=100 spells.

Just some observations.

Re: Battlefield positioning observations
 

I dunno where you got that idea of moving mages closer to the battle, but usually my mages wait for the enemy to come to them. It's basically suicide to put a mage up front.

Re: Battlefield positioning observations
 

<font size="2" face="sans-serif, arial, verdana">How's that? Set the army up so that the mage could cast something nasty before the advance elements of the enemy force even reach your position. If you have a squad on hold and attack orders right behind him, they would engage the enemy right before they get to the mage. Even then, however, only cavalry or fliers would present a serious threat.

Re: Battlefield positioning observations
 

Not all mages are easy to kill. Take Vanjarl's for instance. Orders of mistform, attack/fire one turn, orb lightning, orb lightning, orb lightning will make them both very hard to hurt (due to mirror images, defense of 21, and only 1 damage per attack), and will put them in range for orb lightning, which is a very dangerous spell up close.

Re: Battlefield positioning observations
 

<font size="2" face="sans-serif, arial, verdana">Works for the mages in the Last of the Tuatha theme too. Daoine Lords and Tuathas.