Your ROAS might actually be good enough right where it is, but you're paying too much for fulfillment, not leveraging last mile reductions, have an incorrect free shipping threshold or countless other micro killers.
Not all products net you the same dollars. There is a sweet spot amongst your products between margin, AOV and CAC. Hunt it ruthlessly.
Secret... CPC, CTR, CPM DO NOT MATTER. This is the only metric you should care about:
The ability to increase AOV (bundling, cross sell/upsell) is a magic unlock for scale. And here is perhaps the most powerful, underused lever.... RAISE THE PRICE!
Tactics are very overrated and you are likely not making accurate data driven decisions anyway (the amount of human error in data analysis for media buying is INSANE). The unlock for significantly better performance is a subtle creative change away.
If you can increase your 30/60/90 day LTV by making more people purchase more often you will have more cash and be able to scale against a lower ROAS. Analyze your post purchase email flow today.