At the moment mouse steering feels like an awkward cross-breed between Free Look and the old Mouse Steering.
When the ship is idle it's annoyingly difficult to adjust it's heading - you must press movement keys to activate the automated controls that steer the ship towards your point of view.
I hope this will be addressed by the end of the beta as it is a huge deal-breaker for me.
Also with the new hyperjump system there needs to be a way to clear jump coordinates, as having coordinates set in prevents you from using boosters in the direction of the jump point.