This is an interesting concept and I think you're right that it will require coding. Are you essentially wanting an existing feature service to populate a new, unsaved, web map at the user's click? Or are you wanting it more intricate than that?
Sorry for the delay, I recently transferred to a different job and haven't had time to look at this. To answer your question (if I'm understanding it correctly) kind of. I want to be able to click on data within a feature service/layer and have that data generate a new, unsaved, web map.