Final goal is be able to have multiple instances of the same form, each with a distinct and separate layout, ie one instance being accordian style, another being a modal popup, and another being multi-stage etc
With content you can create many search and list types, each of these can have it's own layout.
With the forms, you have admin and site, you can create variations for that form and only apply one.
I could, in a single template file and with if statements, control the layout that way (which might be the way ultimately) though not sure how to do it based on value from url. I imagine it's easy once you know how...
I wondered if I could control the layout another way for each instance of the form. If I could control the fields layout in a module override then that would be cool.
You are talking like you are talking to yourself. Please give me examples, where did you see this? Any URL as example please?
The admin form is for you or your employs in the backend and it follows your front end or its a bit more complicated, so its not important currently.
What I understand from your question is: you want to have multiple instances of the same form on 1 page and create multiple variations of it but apply only one to it. That sounds very disinherit, but interesting, really.
I'd like to help you in this, keep me informed please.