I am lost. Where is your proposition coming from? You apparently identified a subset of positive-SIM-income cities that earn too much Hive. It can not be a small one as going after it would decrease diversity. It has to be a large one. If it happens to be "Everyone that owns more cards than I do" kind of group, applying SIM-like tax will not help (at 70% or 90% or 100%) - they will still outperform you (Hive income is highly secondary to most).

The game is centered around people laying their hands on a 200k rewards pool - is anyone going to play if you tell them it is not meant to be distributed?