People were expecting some submission guidelines to stick with and avoid rejections, but this requirement of moving features to plugins is a different story, unless you are not planning to rename the marketplace to SkinForest
I’m wondering, why you are not opening a customer survey and asking their opinions?
The API is mostly unusable now, imo. I don’t have an idea how the chirp.js works, but it just works and not require an API usage. Customization is easy too and can be implemented to your current widget, like I did. I took me ~ 30 min to figure out how it works and implement it to my widget.