10isfreak, thanks for starting this thread. I was actually thinking about this as well.
As for the question, I'm in the same camp as Ash. Basically, swing path for topspin, racquet angle for launch angle. There is interaction to be sure, but when I hit I need to keep it as simple as possible. When I want more topspin I try to get a larger component of the swing's velocity to go up and for flatter shots I hit through the ball more. I use the racquet angle to adjust the launch angle, which is what I'm specifically looking at as I hit.
After that it's up to nature and God as to where the ball lands.