wel for Idea 4 is where Rita is a total redo of power rangers, where it's like how battle star galactica did with a new story, new actors, and new looks for good and evil alike.
and for idea one is where the rangers are recruited either from the best of all the planets ( Earth, aquatar, KO-35, etc.), or the best of earth.
but Idea 3 would of been just all the exsisting ranger teams coming together to face foes, no single team could with stand.