Re: Storm VS Mystique
I think the Xavier/Magneto dynamic will take centre stage in DoFP, as we have versions in both timelines.
There is (as yet anyway) no future Mystique, and no past Storm, so those characters don't have a counterpart to play against in this story about destiny and choice.
But of all the women, it's likely Mystique gets the biggest share - because Jennifer is a hot commodity right now, because we need to see how the past version became hardened into a cold, kick-ass b***h, and maybe because Mystique's actions are pivotal in the comic books.
I would like Storm to get some dimension and development in a future movie. Maybe the next one can open with a Storm origin scene, which turns out to be the character is explaining her background to a new set of students. And perhaps the main plot will link back to that in some way.