We already make limited use of YAML's aliases and anchors. We could take things further and reduce the repetition. I've prototyped something here. It reduces the file length by 92 lines (from 648 to 556).
I think it's an improvement but anchors and aliases seem to be a bit polarising. Let's see how the rest of the team feel. If we're happy with the approach, the change should be low-risk. If the changes have been made correctly, fly set-pipeline should respond with no changes to apply.