How to handle target systems that have access rights organized on two different levels?

I have accesses to groups, but access to these groups is possible in 4 different modes (view, edit, etc).
To handle this kind of use case, we used to use the group/access mode combinations. But in this case since there are more than 300 groups, I should create more than 1200 combinations.

Has any improvement been implemented in version 9.2 that allows us to more effectively manage these types of accesses (aka, target systems that have access rights organized on two different levels)? 

Thanks,

Martina