This is one of the best ideas I have heard so far. Unfortuanatly the EE is to close to release that they will not change the main story any more, I guess.
By the way: What is source and what is the difference between normal magic and source magic? I have found a wiki but it is only about the games and not the world. D:OS is the only Larian game I played so far.
It's not very well explained (which is good). It's the unique thing that the Divinity universe has. In DivDiv it was basically healing magic and it wasn't explored further than that in the other games. If they had explored it in the way I said, the logical conclusion would've been that YOU (the player/s) are the Source; that's one hell of a gameplay and story interweaving example and quite the artistic statement and realization. The healing thing would be driven even further, you are actually fixing (healing) the problems of the universe by simply playing the games.