gvpr does support the C pre-processor (#include). It will even interpret the #line directives left by the pre-processor.
I am not sure what you mean by this. The last semantically meaningful change to cmd/gvpr/lib was 7 years ago. It’s pretty isolated from the rest of the code base and we’re not space-constrained. From my perspective, you could dump all your 200+ scripts in there as-is. A lack of commenting or consistent formatting isn’t going to meaningfully impact code quality in the repo.