I had many clients who did things like you. In your world, you may not need a development branch. I think that you use the wizard as a development branch, and this is normal for you.
However, some organizations have a high ceremony, and everything requires discussion and approval. In these places, the development branch can function as a place where all the working code is merged before you separate it in order to free the branches and eventually learn. On the graph that you showed, there are branches of functions where the code lives before it works. The development branch is the place where it fits when it is suitable for communicating with well-designed code. From there, at some point, a snapshot from the development feeds a release branch that can remain active for weeks or months while people approach and process QA cycles, the final set of functions, etc. In the end, the release branch advances to the master, which is production at any time.
Since your current setup works for you, maybe that's all you need. It certainly does for a less cluttered world.