Variants are a systems problem
If every ad size is rebuilt by hand, volume will always lose to deadlines. Master templates with placement-correct export presets turn a week of resizing into an afternoon.
Where AI earns its place
Use it for the mechanical layers: rough cuts, captions, background plates, voiceover localisation. Keep concept, script, and final edit human — that is where brand actually lives.
Ship on a calendar
A fixed monthly batch beats heroic launches. It gives media a predictable supply of tests and gives the studio a schedule it can staff.