As satellite density increases every satellite will need a collision avoidance system anyway. And getting from geo to leo is way less difficult than launching to leo from the ground.
It's not clear. Maybe satellites will be assigned flypaths, like in aviation? Or you can have either a short-lived satellite, a GEO sat, a well-maintained constellation for communications or observations, singular exceptions like Hubble - or go fly away from Earth? Or something else? Not sure it's good idea for space elevator engineers to trust as much that all satellites will always behave as they, space elevator engineers, absolutely require. The error cost is pretty high.
