I feel I've built something similar using fluxcd + cuelang. FluxCD allows having order through depends on and how you organize your Kustomization resource.
I still believe the FluxCD project needs a UI that matches what you can get from the cli. CLI has so many features that you might or might not get fully from the available UI's.
Agreed. I'm hoping the old Weaveworks GUI makes a comeback in the near future under the new organisation, as it looked to do a better job than anything else I've seen so far.