As I've suggested before here multiple times, I like the idea of using fluffy sand that encourages buried lies. Good players generally fly the ball into bunkers, and will get some buried lies. Poor players often roll the ball into bunkers, and will generally have a fairly clean lie. That equalizes the bunker penalty somewhat, versus the current situation where a clean lie in a bunker is almost no penalty for a good player, but a huge (mostly psychological) penalty for the poor player.
From a buried lie in a fairway bunker, you will not be able to reach the green, but recovery and par is still quite possible. It is enough of a penalty to make the player fear a fairway bunker in a way that good players no longer do, but isn't a guaranteed loss of stroke so prudent aggressiveness is still rewarded. Around the green the buried lie is a test of game planning, to attempt to insure that your misses are in an appropriate location. You aren't going to get up and down from a buried lie when you are short sided, but if you miss elsewhere and have a little green to work with, a well played shot will give you a good chance at making the following putt.