"Are there any other casino-hotels that have four different check-in areas for different level players? Most Harrahs properties in NV have two..."

The Harrahs Vegas properties seem to have at least 3 check-ins (Standard, Platinum and Diamond)
I have not seen a Seven Stars check-in, probably hidden away so they will not be bothered.

Harrahs Rincon has 2 check-ins (Standard, and 1 VIP for Platinum, Diamond and Seven Stars). Do not know about other Harrahs properties.

Will know about Harrahs South Lake Tahoe the first week of October.