In terms of 3D airports with buildings, I’m not exactly sure who creates them but it seems fairly limited. With that in mind, there are staff hired to code aircraft.
With all this in mind, this isn’t a simple task for one to complete, and I can assume it isn’t able to be done through the app. For example, just creating an airport layout requires software for a computer and is completed by our IFAET team. This feature request overall just feels to general for me. How will we limit who can do it and ensure the quality we have now?
And lastly, in terms of liveries on aircraft, a feature request is already out there (not saying this is a duplicate) OpenSource Livery Templates. Pretty cool to check that one out as well.