So, both my players and I take advantage of being able to pass to the environment as a story element. Accelerating the disaster that's coming on, or empowering the heroes via moving into a different zone, etc.
What are people's thoughts on being able to pass to the environment turn as opposed to it always acting first or last?
By the rules, you can pass to the Environment/Scene as you would any other actor. Doing what you describe regarding bumping into a different GYRO zone is an intended feature and ruling that the Scene always acts first or last would mean that players can't set things up so that they get a lot of turns in a row (have GM-controlled stuff go early in one round so that they can bunch up hero actions at the end of one round and the start of the next).