a nightmare for everybody else.
How?
The purpose of the coin is to be used as a currency. Explain your nightmare situation or how this proposal interferes with the purpose of this coin.
I think the problem of centralization and consolidation is much higher with masternodes than with miners.
Show me numbers.
Three big mining pools colluding can fork the DRK blockchain. How many MN ops would be needed to pervert the network? A much higher percentage, that's how the MN system was designed, you need far more than 51% to cause problems.
Top 100 wallets buy 4 times the masternodes that are now in existence. Top 10 wallets buy 1.5 times the masternodes that are now in existence. And contrary to miners it would just take them an evening to set everything up and mess with the system and a few seconds to disappear again.