Love this!! Most stable modded SLRR i've ever come across, out of testing both my own game setups, versions, and other peoples setups. Plus, it still manages to pack in a tonne of more content than most other setups.
I only have two very very small issues:
One issue is the way engines are organised (But I guess that's a luxury you can't really afford with so many engines). One thing that would make this issue less dramatic is if the compatibility icons worked in the engine menus.
The other issue is cars at the dealerships don't really update that often, and some cars stay there forever unless you buy them.
Aside from those two, this setup is easily above a 10/10. Bloody good job.