Uncomplicate the program. HGP needs only the same three levels it's had. Most of Hyatt's U.S. footprint = HP and HH where elite benefits are minimal. Three tiers is plenty to distinguish at the full service Hyatts.
For those full service HY properties, there's a key word missing from most World of Hyatt tiers: b-r-e-a-k-f-a-s-t. Be competitive with HH and MC and add it to what is now and should continue, the Platinum tier, as well as, of course, Diamond.
I agree with others that the nomenclature of the too-many tiers makes no sense.