Agree with your sentiment here. The cartel reminds me of how splinterland's success works with being in depth. There are the tribe tokens and curation proceeds that supplement the cartels holdings. The posts created by the cartel and operators draws in money too by token earnings. The cartel's foundation is based on actual game assets that create yield too.
The only downside I can think of is trusting the cartel creators to use the funds wisely. The use of a voting system helps but that can't be done with every decision the cartel makes. Then again, the cost of time by trying keep up with every decent hive game on your own is traded with the convenience that the cartel offers.