I think I can wear multiple hats. That should not be an issue.
hmm... i will have to think more on this.
The fact is I am not happy with my current job.
Don't subsidize a startup by taking a pay cut, and especially don't do it by digging into your savings, unless you're going to be one of the founders and get a larger equity grant to begin with.
Also, you said the startup won't provide benefits. Do you have other means of healthcare / health insurance? If not, then regardless of compensation, the lack of health benefits would be a very extreme risk to take on for yourself and your family.
If you want to pick up new technologies, inform your family that you will be parked at the kitchen table every Saturday for the next 4 months teaching yourself Python, web developemnt, containerization, whatever (what to learn is a separate discussion). Libraries, internet: learning is free! No need to take a paycut for that.