The bus factor is interesting. Someone could just get actually in an accident, or they could have a health crisis,. Like, could be a place where it stops. If you're picking the most challenging thing to use because of the most fun, you might want to be considering that as well. How simple is it for somebody else to sit down, pick up your work, and keep going with the libraries you've chosen to use? That's also important. Sometimes some things that you have to do all complex, but if the tools are, there is to hold a store.