What about the ability of nodes and miners to decide whether transactions are valid or invalid? If they can't do that, wouldn't it be possible to spam the blockchain?
If you want to prevent that by requiring mandatory miner fees, you need to add the miner fee part of the transaction without randomization, as you don't know which miner is going to add your transaction to a block. Would that be feasible?

Or did I misunderstand your proposal thoroughly? I must admit that I did not analyze it in depth.

Onkel Paul