I think the distinction for me is getting from the mindset of "I'll look for a package for this" as opposed to "let me write some elisp for this."
Prot has an intro book on elisp[1] which I want to go through, because some specifics of text processing and buffer usage are a bit unique - it is a lisp for a text editor, after all! But it is still just a lisp, and it even has a lot of common lisp functions in cl-* namespace!
if you test it and it works, you should publish it.