Bingowings said:

If strange animal noises were added to sound mix the audience may be lead to believe there are all manner of unseen giant creatures which may pay off if someone did manage to get the AT-AT to stomp through the forest convincingly.

Really good idea.

You wouldn't even have to show anything. But so far we have this forest moon on which only Ewoks live, apparently. It's incredible, the lack of imagination that went into Jedi. There is no whimsical detail anywhere on Endor.