Peace of mind isn't a trading strategy but a state of the mind that all traders need to be in to make better decisions so they don't lose but become victorious in their trade hence you shouldn't call peace of mind as a strategy before some newbies that are not well informed will think that peace of mind is a trading strategy. I haven't seen any strategy that I'll declare as the best trading strategy because I know how different things can work in a specific way for people with different mindset. There are some strategies that doesn't fit everybody trying to become a trader, to be doing. Some strategy that got to do with high leverage isn't for everybody's as there are people that'll lose when they try it because they're not preparing to risk that high when trading. Some of the most popular trading strategy, are Scalping, Day trading, New trading, position trading and so many other strategies that are very efficient.