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.
You cannot buy enough Masternodes to have a realistic chance of subverting the network. There aren't enough DRK in existence. Any attempt would cost you many times more than the whole currency is worth. Evan thought that one well and truly through.

And you can switch where your mining farm is pointed about 10000x times faster than you can set up a thousand Mastetnodes.