When we were kids we rode bareback every day.  Even if it was just to cool them out. 

I think this provides a great sense of balance and creates a new form of communication with your horse.

True horse lovers should see the Disney Classic (at least I think it's a classic) Horse in The Grey Flannel Suit.  When the young girl needs to learn balance, SJ has her ride her hunter bareback around barrels (trotting) then finish over a cross rail.  Dee and I did that constantly when we were kids.  And balance was one thing we definitely had.

Get on bareback and start talking to your horse....your natural aids will become much apparent then!