You need to find a strategy that gives you an edge to constantly be profitable vs the risk taken. Then, look for the product that best fits your strategy by forward and if possible, back testing. Then trade it in a live market and adjust as time passes.
Since none of know what you have developed and what works best, and how it works with any of those symbols, it's hard to respond in a way that will help you. I would monitor all three and current market condition, then trade the one that provides the best edge for what is happening right now. Crude and financial indexes will be volatile at different times for different reasons.