Love your poker analogy.
I have recently being implementing these little satellite businesses as I call them.
My thinking is that I spend 80% of my side hustle time on a main project and 20% on these satellite projects. I say satellite because they still gain value from my main skillset and are not completely unrelated.
Getting better in marketing helps me improve the marketing in the satellite as well as the main businesses.
If any of these satellite business becomes successful I can divert more resources to them, if they end up only making me a few extra bucks a month that's fine too. If they fail I have little attachment to them.