Monroville said:

6 to 12 (or 2 for every AT-AT: one to cover each side) ... the idea is to show an actual task force. 5 AT-ATs alone could get taken out easily by ground troops; having a good squad of AT-STs would be akin to blitzkrieg tactics used by the Nazis, as well as account for taking out any troops trying to get underneath.

If the Empire is sending in a small group to rush the rebels, I can understand only 5 AT-ATs being there, with said group of fast moving vehicles to cover said AT-ATs ... even so, it would be nice to see a more realistic depiction of military behavior.

Sure, and it sounds great, but it would entail showing several AT-STs from various angles in several shots of the battle sequence....and I just don't know how Adywan can achieve that.

Perhaps other AT-ATs (and AT-STs) have been deployed to approach the Rebel Base from other directions too, unseen by us....