That's why I decided to support static graphs in the first place. After all, in most cases, static graph programming is enough, and being a user-friendly really matters.

This is a pitfall. I’m working on something similar (internal solution) and dynamic task graph bites back hard very quickly.

Domain I’m working on is very prone to a failure so having simple visualization/interaction (e.g. click to inspect/retry) is an important feature.

For that task graph needs to be resolved and static before actual execution phase. Nothing prevents multi-loop resolution (i.e. task graph which result is a task graph). Just make sure artifact sits in-between.