@dansup I like this idea; I think you’ll find that adoption correlates with free open source though. Perhaps keep the source open & free, but share your roadmap with ideal donation amounts for items on your roadmap that correspond to effort/costs.
Like “code is at this milestone” and “funded up to this milestone” (to show whether you’ve been underfunded for your efforts, or if the community has been generous)
(You should subtract any running costs too!)