Minor bug - when turning, the rotation AI ignores the ship's current turn speed. For example, my ship is currently at 0 facing and turning clockwise quickly, when I issue a move order facing -120 degrees. Instead of continuing to thrust clockwise (taking advantage of momentum), my ship will try to turn counterclockwise at first, slowing the turn.
Here's an example of what I mean:
http://www.mediafire.com/file/pr2mzs1d1jvd9jp/turn%20bug.savedgame
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There's also a very annoying "bug" where ships will never reach their max turn speed because they want to decelerate to stop at the target (even though the player keeps moving the target to keep the ship spinning). This ship is an example of what I'm talking about - even though it has a huge theoretical max turn speed, it can never achieve it because it's trying to stop at the target point. Try and make it spin quickly and you'll see what I mean.

The best solution I can think of to this is to add an autofire option to thrusters, which I'm pretty sure has been requested already. I don't remember if/what the reason was to not add it though.