Check my thread, This customisation is way too messed up, One single app to customize it all is necessary, there's Theme Park and so many of add-ons.
All those should be added to one single app for easy setup. Where your created theme should be saved as a single project, and back it up for future use
Only third party is your option then. And it should be that way. Stock or official should have restrictions. If anyone wants they have to find other ways.
