I know you haven't responded to me directly, but I wanted to let you know that I've been in your same exact spot. Stuck feeling like I'm not making any real progress and that I need to just take a leap of faith. I'm in the middle of that right now, in fact--I've literally decided I am not taking a new job in 2020 because I'm sick of the yoyo-ing and want to make this work. It can be motivating, and sometimes you do just have to take that jump.
I think it does have to be a calculated risk though, because if you don't have discipline and a plan in place, you'll flounder and probably end up more overwhelmed and stressed than you ever did before, especially if you have that fear of success.
If you truly feel like you have a lot of to gain by quitting, and like it would help propel you, you can still have that on the table. It's just, from what you've said, it doesn't seem like it's actually a burden on you. Maybe there's another way you can motivate yourself to take it to the next level.
I want to reiterate too that I don't think your overall idea was a bad one, but that it needed tweaking in order to be ethical to everyone involved. I'm glad to hear you've invested a lot in artists, even if it hasn't always worked out for you--that's good. You're dependable then. I honestly think the model of paying for Kickstarter samples, running the kickstarter, then producing it would be a good fit for you if you feel like you've already invested a lot and don't want to risk more right now.