Currently the fee is pretty high, because the more proposals we have the higher load we have on the system. I am not sure our current system could support more than a few hundred proposals, or maybe far less, we don't have a testnet big enough to know, and the math hasn't been done to simulate it because we have been too busy. Eventually with more and more proposals some of the weaker masternodes will start to have issues. Free proposals are just not technically possible as this could possibly lead to at least a 1000 proposals/month.
Then there's the second issue : MNO's can't be bothered to look at 1000s of proposals. I also am investigating how to solve this, and hopefully have a solution that everyone likes. Expect a whitepaper and DIP early next year. (Because we are all busy on evolution/current system).
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