Player created content is a problem in procedurally generated game worlds. All procedurally generated content is static (or cyclic, e.g. planet orbits). It can only change if the procedures generating it are changed. That is why the new stations along the way to Colonia will not be in-game until 2.2 is released. Overrides for dynamic and persistent content can be placed in a separate database but then the procedural generation process would have to check the database for overrides for every modifiable item in the game world. That would quickly lead to performance problems. Dynamic but non-persistent changes are supported in ED but they are lost if you leave the instance (hence RES resetting is possible).
All dynamic content in ED (Rank progression, Powerplay stats, CGs, BGS, Missions, etc) reside in the database and only show up in the game as text strings. Already we see performance problems with the Mission system and that is without them causing persistent changes to the game world. ED would need a full redesign to make the game world support dynamic and persistent content.
Using coords and planet info the only dynamic thing to render would be base of cmdr y at coords x y z
It would stil give performance issues on overpopulated worlds though