Then I just have one node and pretend to be thousands of nodes. You've just reinvented mining but in a cumbersome way, and failed to benefit the system.
If you have a node, you would tack on PoN to any transactions you care about (to you or away from you) and thus use your privileges to get them confirmed quick, but you would not have incentive to use your processing power to spam up the reserved space with transactions between strangers. A market for PoN may develop, but that would just incentivise nodes more.