Idea for next Mass Effect game

I dont play ME myself, but I know people who have/do. Here is my idea for the next ME game. Instead of having it so you can play different characters/spieces why not have it continue on from the ending of ME 3 where Shepard lives and the galaxy has to rebuild. But also to where it picks up the gameplay it's self with how ever the player ended ME 3? Just a possible idea