Actor turn rate is too slow
NPCs and creatures can turn in any direction instantly in Morrowind, but OpenMW seems to give them a minimum turn rate, so when something wants to do a sharp direction change like 180°, it has to walk a small circle instead of just changing directions. It's easy to see on the guard that walks you through the boat, at the start when he turns around to walk away and at the end when he gets on his final position.
I don't dislike the current behaviour of OpenMW as if feels more natural, but it causes issues with mobs requiring more space to move around and missing projectiles when they cast faster than they can turn, so there should at least be an option to replicate the original behaviour.