Home and away leg aggregate system.
I start a wager for a coin prize of my choosing, Could be 10k meaning a prize pool of 20k once my opponent accepts or for the heavy hitters 500k meaning a prize pool of 1Mill, Winner takes home the prize in this heads up battle.
You could also do it with 4 teams like the group stage of the champions league with 6 games played home and away, Pay out 1st as 60% of prize pool 2nd 30% and 3rd 10%, Or make top 2 play off heads up for total prize pool.
Pink slips is another thing I'd consider, I put up a player and my opponent matches that with a player of equal value, You win you get both players.
In my head it sounds pretty awesome, Can only be done if no loss glitches are extinct.