For 30 ads/week with tight turnaround, use Canva AI as your primary tool: its brand kit, templates, and one-click resizing give the speed and consistency you need. Use Midjourney selectively for hero images where you want standout art—expect more iteration and manual templating. Workflow: batch-generate concepts in Midjourney, pick 4–6 winners, import into Canva for templating/resizes. Use ChatGPT to create prompts and bulk ad copy.

See Midjourney comparison: Compare Midjourney and Leonardo AI