I found wearing shoes without any heel lift (nearly all the time) helped a lot, hard to find something suitable for work if its a formal environment though. Helped me with my general feeling of stability around the ankle, to such an extent I just can’t wear the specialized bg cycling shoes anymore.
The trouble with bosu and stretching regimes and core work etc (when done at home), is are you really going to keep it up long term (I never do). I think it is better to find something else to do to work other exercise groups, could be running, swimming, gym work or even a weekly game of squash.