Who would move off-planet?

The only way those would work is on the macro-scale. Weather is a side effect of the gestalt atmosphere, while earthquakes/volcanoes are similarly products of Tectonic Activity. The former can be made less intense by taking away the primary source of energy, which is Heat. Of course, we want some to avoid an ice age, and drive the convection to produce rainfall, but it's becomming pretty obvious that with more heat comes more intense storms, flooding, and so forth.

Tectonics, I just don't know how to go about that. I mean we're not talking about moving mountains here, but stopping the motion of entire continents. Good luck with that! I theorize that a lot of energy could be taken out by deactivating, or dialing back the magnetic feild, but that also produces effects we depend apon for survival, such as radiation shielding.

The thing is, were already terraforming the atmosphere, only as a side effect of our technology, and primary energy source. We really need to learn how to do it intentionally, to improve our environment, instead of messing it up.

I think the Earth is good for me because I get all what I need and I enjoy every minute I get here.