They most likely won't create a game past the ME3 point in the ME universe anyomre.
so...
If we, the loyal fans who provide the majority of feedback on things and go to all the events, were to.......I don't know

...... ignore the endings that were given to us and just create our own. Couldn't that thought process eventually become a canon of its own in this universe.
Casey did say there was no canon in the ME universe.