[Taqwus]

The AI should pay more attention to supply lines and the risk of strategic encirclement.

If it's going to risk being cut off, it really should make an attempt to forge supply items and bring them along (which requires nature magic; perhaps AIs should make more use of indy druids et al). This is particularly true when using troops with a low base morale, because of the 4 point penalty...

e.g. Last night playing the demo solo as Jotunheim (Utgard theme), I found and attacked the Machakans. At one point, they attacked a forward fort of mine. Their sieging force, mostly Machakan light foot with spider knights, was adjacent to only one Machakan-held province, which in turn was adjacent to their only castle (Machaka itself). In this single-province bridge lay another Machakan force led by the spider lady herself. Next to this bridge lay my main force.

The next turn, my main army (led by my Son of Niefel, fairly small but composed mostly of giants and with a number of Skratti and Godes et al) attacked -- not the besiegers, but the bridge. The Machakan force on that bridge, before the attack hit, joined the besiegers. That meant that the besiegers, while they were now making decent progress against the walls, were completely surrounded -- and I annihilated them the following turn, as the morale-4 troops were trivial to rout. Well in excess of half of the total Machakan armed forces, including a decent national hero, were obliterated at little cost since they had nowhere to run... That made it far easier to take Machaka a couple of turns later.