I don’t like the idea of a tenuous bunch of satellites keeping an atmosphere in play. Relying on technology to keep atmosphere on a planet sounds super risky. Like if we wanted to live in such a place, we’d live on a space station. Planets are supposed to be safe and solid.
The current theory is if we grab a few asteroids and hit mars just right, we can speed up its rotation enough to restart the dynamo. Sounds way cheaper than a permanent planetwide shield.