One of the plays I hate the most is punting the ball out of bounds, simply to avoid a return. It takes away from the return game, and we all know how exciting the return game can be, if it is allowed to proceed.
10 Yard penalty of the ball goes out of bounds in the air with the exception of the "Coffin Corner". If the kicker can put it out between the Goal and the 5, the kick stands as is, since that is a difficult kick to do properly.
Out of bounds in the End Zone is a single, no change.
There should also be a disadvantage (other than the 2 points) for the safety. Perhaps kicking off from the 20 (or allowing the other team to scrimmage from the 50).