The AI does not use ships well and also has a small bug with its movement.

For one thing, the AI may send squadrons to far away planets that are of no use at the time and will not be taken, wasting ships, (scouting is fine, with a scout..) This may be fine if no one is worried about the AI, but could be better..

The bug is a bit worse though:
Occassionally there would be 5 or so frigates at one of the planets constantly switching destinations between two or three nearby planets, which resulted in them moving nowhere. This happened twice in one game, I'm not sure what brought them out of it but it lasted for a good length of time.