Complex strategies like butterflies, condors and such are just for pros who have a smaller spread then retail traders. Spread will cost you about 15-20% of your projected profit if you are a retail trader. No matter how much one knows about expectancy, greeks and hedging, if you do not know how to spot reversals you will never make money in options markets. If you know how to spot or forecast reversals, all you need to know is how to buy a call or put or how to write credit spread. All the theory goes out of windows if you cannot spot reversals.