Well, here's the rub.
The reason that bounces come in so many different varieties is that bunkers come in many different varieties.
Harder, coarser bunkers require less bounce, while soft, fluffy bunkers require more.
Clubs with more bounce are tougher to 'open up', as the leading edge comes that much more off the ground (increasing your chance of blading the ball). Conversely,
clubs with less bounce are easier to open up, but will dig in softer conditions, lending themselves to a greater chance of going fat.
I play with a 56° SW and a 60° LW - the LW has 9° of bounce, the SW has 11° (each bent 1° weak). I actually preferred a LW with 6° of bounce (I plan on grinding the sole of my current LW), just so I had a 'digger' option and 'bounce' option out of the traps, depending on what I was looking at.