You can't know the optimal stop ex-ante.
A thorough backtest (1 000 or 2 000 historical trades for instance) will show you the optimal stop, period.
budget stop should be how much you are willing to risk on any trade x confidence
The market does not give a hoot about the amount of money we are willing to risk, so the only way to solve the problem is to look for the optimal stop AND the optimal % of money that we should risk per trade.
Trading is a mathematical game, so the trader must know - IN ADVANCE - the optimal parameters to use for maximum profit and minimum drawdown, any other way of trading will always produce inferior or negative results.
