I've definitely considered crowdfunding development in a few ways, and that does remain an option. It can be hard to rely on sources like Patreon in that the income can fluctuate quite a lot so it's harder to predict financially, but in theory, absolutely possible!
Open sourcing it is a non-option for legal reasons. That being said, longer-term I personally endeavor to focus on games as FOSS in general, so in many way I see Core Decay as eventually providing the means to do exactly that :)
