Sounds like your tech stack is already worked out on that, so why not white label it to debtors firms? The typical SaaS billing levels (Starter / Pro / Enterprise) would work, and you could offer a paid-by-the-filing level, too. Roll in the pre-filing counseling and the electronic filing and you've got a really good and attractive solution.
Especially as this is built for self-service. If a lawyer could have an in-person counseling session with a prospective client, then point him/her at a webpage to fill out the details and upload docs, that would save an enormous amount of time.
It's been a couple of years since I look at the filing software, but the industry was dominated by a couple of big players and the client-facing solutions were minimal and sketchy. The big advantage was being able to file electronically. But it still needed a couple of dedicated paralegals / clerks to track down all the papers and enter all the details.
Good luck to you!