Allow us to use Visual Studio, in particular source control and unit testing on a Flow.
As the number and complexities of flows increase, the ability to manage a set of flows as a project becomes increasingly important. As a developer, it is necessary to modularize and reuse code, maintain verson control, and be able to quickly change the runtime environment from test to production.
While Flow in its current state is a massive step forward and has incredible potential, it is also cumbersome to use for anything but a small number of independent actions. It is difficult to identify dependencies and references, and there are things that are just not practical (like changing a trigger or creating reusable building blocks that can be called from other flows).
Building a source code editor into Visual Studio and being able to manage a project and then publish to the Flow service quickly and easily would really help deliver a robust enterprise-class solution.