After a long night of transporting goods, my poor old mouse was starting to feel worn out last night and the right mouse button was getting less responsive.  It'd be nice if we had a mouse lock key for travelling.  A toggle switch that does the same thing as holding down the right mouse button.  That way, when travelling, we could turn on autorun and mouse lock and move around without pressing any buttons by simply moving the mouse to turn.  It just makes steering a little easier at times when there's no need to click anything.

And while I'm at it, though I know it's been suggested before, the ability to bind mouse buttons as hotkeys really can't be added soon enough.