What about consider “Rack + Rack State” to define uniqueness for pre-load and shared parameters purposes?
Example:
I create a Strings rack with two states:
- Fast Attack, Fast Release
- Fast Attack, Slow Release
Then I want to split the keyboard using both rack states … but I can’t. 
Bonus:
The rack state selected parameters are shared between the multiple instances of “rack + rack state”. The remaining parameters are shared between all rack instances.
Considering the exemple above, if I tweak the volume of the Strings rack … all instances of the Strings rack will have the same volume. If I tweak the release of the Strings rack … only the instances with the same rack state will have the same release value.
