you mentioned you wish you could go full-time on this… How do you foresee this becoming competitive or differentiated from all of the others?
Nobody is asking you to do that, you can assess that for yourself if you're interested in looking at the project, if not, there's not much point subjecting the author to this sort of interrogation.
Consider not projecting emotional states on people you expect to reply to you.
“what do you think the advantages of your new library are that outweigh the years of development behind existing libraries?”
Like the sibling comment says, that's an obviously loaded question. But more importantly - Show HN is for all kinds of projects - from polished commercial offerings to learning projects or scratch-an-itch projects in their early stages of development. It doesn't make sense (nor is it particularly respectful of the author or inviting to new authors) to treat the posts of personal projects like a sales call and present them a list of generic, reflexive checkmarks and requirements questions. A Show HN of that sort is an invitation to take a look at something, provide feedback, chitchat with the developer if you have an interest in the particular topic. If fully-baked things are more your speed, you can just find a Show HN that showhns that.
> I am aware there are already libraries that can draw to multiple contexts interchangeably, but I've added a few little niceties to Ripl that (as far as I know) some other libraries don't have such as CSS-like query selectors, DOM-like event bubbling, and keyframe animation support.