It occurs that if very many are using the same texture sheets, that would make it a lot less difficult if someone decided to replace those textures with something higher resolution.......?
The Uwespeed ones all use one or two texture sheets and were autogenerated by a program. They are intended as completely generic buildings of various sizes not covered by the higher quality regional models. Those particular textures could easily be improved, however the models are very simple, basically 4 walls and a roof. Uwe had created the German textures with a goal of simply replacing the texture sheet with something like an Italian one without rebuilding all the models again.
The UK/PL/DE/CH regional buildings all have more detail, but the majority are simplified shapes (some have chimneys, garages, entrance areas). Remembering of course, that in X-Plane you can have thousands of these objects in small areas, so keeping the triangle and texture size down was incredibly important. I'm sure the same still stands for Outerra. Once such buildings are placed from something like OSM data, as they are with World2XPlane, then I'd imagine performance will become an issue.
The Blacky75 models (and there are hundreds of them) were all created by hand in Sketchup and share a few texture sheets. The buildings are again generic European and mostly simple squares with a roof and Chimney. These textures can also be improved, changed and regionalised.
I believe it's important for people to know that the building library was made for flight simulation, and the buildings aren't meant to be seen close up, but from 100ft+ above plus.
