We do have forms that are set-and-forget, too, but the majority do need the query string. Perhaps ask your API devs for an endpoint that returns just the URL of a form requested by ID? ??
That’s pretty much what I’ve implemented currently, yes. My concern with that (and why I didn’t submit a PR) is that I wasn’t sure it was the most user-friendly way in which to allow the user to add custom fields. By that, I mean that not all Pardot users may understand what a query string is, or how to build one, which is why this plugin is likely very important to their workflow.
I have been pondering whether allowing a comma/colon separated list of key/value pairs might be more beneficial to some users, using that to build the query string in the back end. In that case, users only have to worry about what their custom fields are called, and what values they wish to pass to each.
What are your thoughts on that?