Visual Composer Add-on - Custom Page Header based on user uploaded image

I use Visual Composer for site development in Wordpress. I'm looking to create a custom add-on --- A way for me to dynamically generate a background row image that takes advantage of VC row-background features. The plugin needs to let me select a row and add a background image as per the current workflow. Until the selecting the image! Instead of the media gallery, the choices need to be --> an image uploaded by an end user as part of a form for a custom post, the featured image, the first image used in a post, etc..) Sorry, I'm not super familiar with all of the various shortcode options... The image needs to be able to have all of the standard VC options for parallax, auto moving background, fixed, etc... It will also need to work with Taxonomies. So if a user does not upload an image as part of their event creation, the image will come from a related taxonomy -- such as organization the person works, products, a group/team they belong to, a venue or part of town, etc... Please know that I'm very diligent when it comes to QA and testing and will pester you with question ;-). In short... please don't bid just b/c you can. Bid if you like the sound of this project and are interested in doing lots of little jobs like this and want to build a long term working relationship. Please include specific references and example to VC in your response. Thanks for the consideration..