Use Webform as Module Config Page? I am building a module that will create webforms for use with the Commerce Webform Order module. These must be somewhat constrained in their structure, so I have developed a form (using FAPI) to configure them.

Well, the form has become rather complex, with several "add another" fields and the like.  The Webform module handles these rather elegantly, and I'd love to use its capabilities for my module's config page, but feel that a traditional webform would be subject to error and fiddling.

The config page must look at a given webform (if specified) and use its content to pre-load values, or create fields, to allow for further settings adjustment (e.g. prices of items, additional fields, etc)

So, is it feasible to somehow invoke the webform module to create something that works like a webform but is under the control of my module?

Thanks in advance.
The Webform module just extends Drupal's Form API. Most of the elements available to a webform can be used in custom-built forms. For example, you can use the WebformMultiple element in any FAPI form. 

@see https://git.drupalcode.org/project/webform/blob/8.x-5.x/src/Element/WebformMultiple.php