How Many ebooks should I write before my first release?

I plan to release my first book in October. It took me two weeks to write because I kept changing the world building. I still need to finish the final battle. It’s sci-if high heat. But, I’ve been busy organizing my movie collection. I’ve got three more stories outlined and can probably write them in a week each. Another month of writing. I’m thinking about releasing them all a month apart to build my library so I can rely on it to market my books. Marketing is going to be the hard part for me. I figure the more books I have written, the better. I may have two more by the time October comes so a total of 6 books writtten before my first release. Is this a good strategy? Also, is selecting the paperback option a good idea for those that like physical copies? Do many erotica writers use it?