Haven't found an answer for this:
Concerning server groups,
Level 30 can add level-1 to levels 10 & 15... as planned. And level 30 can also add level-1 to levels 50, 70 & 75, not planned.
Level -1 contains negate values that limit user permissions i.e. for policing purposes; which is still quite effective and unwanted when misapplied to higher levels. Is there any way to keep my level 30's ability to add lower ranks to this level-1 but remove its ability to add anyone with a higher rank, an immunity if you will for level 50's on up. Specific client permissions perhaps?

Yes the higher ranks can remove the level-1 group from themselves even though other permissions are denied/limited. But ultimately I'd like to avoid it even getting to that point, as it becomes an annoying abuse of power regardless of intention.