"but isnt it jsu proving a point thats been proven?"
You'd be surprised how many people willingly ignore Lucas on this one. They apparently want a different balance or Luke to be the Chosen One.
"In the Eastern Philosphy there is balance at the end of ROTS with Obi-wan/Yoda vs. Darth Vader/Siddious."
It's not simply numbers - it's the acts of the individuals. There is no balance at the end of ROTS because Vader and Sidious are just beginning to kill hundreds of Jedi, and will soon be targeting others whom they consider their enemy, like the Senators Palps was referring to. This culminates in Tarking destroying Alderaan in ANH.
Now, if Palps and Vader were not in charge of the Republic/Empire with a huge clone army to back their every whim, then your two-on-two scenario would make more sense, because it would simply be two Sith vs. two Jedi. Obviously, this is not the case.
Besides, if it were simply based on numbers, then there is no balance at the end of ROTJ because a Jedi exists without a Sith to balance him. Does this mean the Force will continue to hunt down and kill Luke like in "Final Destination"?