Tom, as you know I am finally working on my first site with GP, and plan to do a LOT more. I agree that what you are providing is almost too good to be true. I have used two themes made by Ben Ritner at Kadence Themes for a few sites I have done, and they were both one time purchase, unlimited use themes. What I started doing was sending him the original theme cost each time I got paid for a site I built as “coffee money”. So essentially I treat it as a one-time use theme. I do this simply because I am making money each time with a product he built, it just seems right. I plan to do the same thing with you each time I finish a site with GP.
I would also suggest maybe doing an annual membership with a discounted renewal rate. I currently use and pay annual memberships for Beaver Builder, Optin Monster, multiple Ninja Forms add-ons, PandaDoc and WP-Rocket… all of which are annual plans with reduced renewals. I would not be able to do what I need to without them, and the minimal annual renewal cost is a no brainer.
As was mentioned above, maybe breaking your model into two divisions is a smart way to keep connected with both audiences. One like it is now with the the free GP theme and $40 add-on’s, and then a higher level annual membership including additional features, child themes and a higher level of support.
The users who complain because they want everything for free, these are not the customers you want to bring along moving forward. GP is one of the best and highest rated themes online right now. People who you want to keep as long term customers will appreciate the fact that you want to take GP to the next level, and be glad to pay a small fee each year knowing you are in it 100%.
Two years ago a mentor of mine was looking at where I was as a freelancer, he told me I don’t charge enough and that is why I am not growing financially. It made no sense to me. He told me if you are charging less than half of what local agencies are, as a businessman I would not feel comfortable hiring you. He told me the clients I am attracting are people who are not serious about their businesses. I doubled my hourly rate, sent out an email, every client said “sure, no problem” accept for two who were the ones always complaining about costs. Business has never been better and no one questions any invoices anymore.