You really are better off getting paid for 1 event (plus expenses!) than getting exposure for 20 free events! No one can sustain free. I’m a children’s author - I guess I’d be deemed successful - I charge properly for school visits here in the UK. After a couple of months, at one or two a week, I am wiped out and want to throw the towel in. Then I find out everyone else is feeling the same. It’s last man standing.
I saw your post about asking for help and was really inspired, I thought you really had it worked out, and you have - in most parts, but you need to be a bit more business like. In business, cash flow is king. Do a few freebies to gain experience or try something new out, but after the free events - and the experience you have - you should be getting paid for what you do.
I would target schools as local as possible to keep costs down and do really cheap kitchen sink science, until you can invest in something more high end every now and then. The audience can only jin in with kitchen sink stuff anyway and there are other channels doing high end stuff. Do what you do best and what the audience loves you for. Really go into those analytics and work out what goes over best. And, BTW, the audience don’t want Klingons, they want YOU!
As for Patreon, yes, I’m constantly wanting to throw in the towel. I’m so grateful to my patrons and have regular conversations with some, But It’s another layer of work keeping me away from what I want to do and really should be doing. Catch 22!
Just keep pushing through and don’t try and be everything to everyone. Do well, what you do best and what your audience loves and wants you for - and always ask for a fee that covers your time and expenses.