Considering switching from Unity to UE4

I’m an experienced developer, author of ActiveWorlds, a 24-year old MMO. For newer products, I’ve been using Unity, but with their latest TOS changes, I am exploring the possibility of switching to UE4. I’m new to UE4, but have been reading the forums and watching many videos about the engine these last few days.

I’m working on a handheld (and later glasses-based) AR platform serving UGC (user-generated content) at earth scale. I have some questions, mostly about handling UGC assets at runtime…

  1. Can an actor be downloaded at runtime on both mobile clients (iOS/Android) and servers?
  2. Can the list of downloadable actors be changed, without having to rebuild the clients and servers?
  3. Can a downloadable actor be a blueprint, nativized blueprint, or C++ code?
  4. Can an actor’s performance (e.g. avg execution time) be monitored?
  5. Can a bad actor (e.g. too much resource consumption) be terminated/preempted?
  6. Can a client simultaneously connect to multiple servers, getting updates from and sending updates to, multiple maps?
  7. Can a map the size of the earth (with mm-accurate longitude, latitude, and altitude) be handled?

Thanks ahead of time for any help you can provide,