Speaking as someone whose Brother used to cheat unmercifully when he was meant to be the Banker, not the Embezzler, and with a Mother who threw the Monopoly in the bin after the five of us children fought once too often over the rules, I quite like the idea of making up the rules of my very own game.
Bristol Games Hub are running a 24 hr Board Games Jam for people who want to do just that – make up a game, and presumably some rules. Though the game development will be done in small teams so there may be some bargaining involved rather than me getting my own way about everything. As long as we include a rule about suitable punishment for hiding large denomination bank notes under the board, I may even let my Brother play the resulting game.
Seriously though, this looks like a great way to test out ideas on paper (or board) with a bunch of games developers. You have to be working in the games industry based in the South West or a student studying games.