Risk in developing a simple SaaS solution

Has anyone developed a simple SaaS solution and had it cloned before gaining market traction?

The app that I developed is extremely simple and took about 5-7 hours of development time. It solves a very specific problem for B2B companies.

My worry is that, since its highly simple right now in its MVP form, I feel like either the customers will defer to "I can build it in house" or worse, an incumbent could easily add it as a feature to an existing app. I also remember the famous dropbox comment, where a user mentioned that they could easily replicate the product with rsync.

Do you just press on and begin finding product-market fit or would you add some more features to deter copycats at this stage?