It wouldn't be practical to force people to make saves with the right stick. Any lag would kill you and you would pretty much have to try to make a save before they even shoot. It's already hard enough to play goalie as it is, I don't think they need to make it harder.
The big problem with goalie currently is that one timers and cross crease passes are overly difficult to stop. It needs to be tweaked for 2010 to make getting over easier to compensate for lag and remove the post magnet nonsense. However goalies should be a bit easier to score on when they are in good position. NHL goalies all have great positioning almost all the time, but they still get scored on because of defensive breakdowns. Plus, there is no defense for the perfect shot.