Thinking of a new subscription service, thoughts?

So, I''ve been doing a lot of soul searching the last few days. Usually I just float around and build on different platforms, build? YEAH, pretty much anything, it's kinda like shiny object syndrome 😂. I specialise in building websites on wordpress using divi, anything from elearning to ecommerce. My new idea is to offer a website build, be that ecommerce, standard sites or elearning sites, and then offer a monthly sub to a design service (pretty much like designjoy - Inspired by). Here's my twist, the websites are built and handover completed within one week. With of course the option to take a design sub. A WEEK? YEAH, a week... I've been doing this a long time and I'm confident in completing projects within a week, especially if the client provides me with all the right information and good communication. Caveat to this is that I would only be able to work with one client at a time per week, so would probably have to have some kind of schedule calendar for clients booking on. SO, what's your thoughts on this? I appreciate anyones feedback and comments!