How do you measure advertising success?

First post here so I apologize if this is a frequest question. I have been selling on Amazon for just over 2 years and have been running ad campaigns basically the whole time. I work directly for the brand who’s products I sell which is in the shoe cleaner market.

I have been primarily measuring success through ACOS as we always try to maintain a sub 30% keeping us profitable. Recently I have worked with an internal team at Amazon to set up Sponsored display ad’s. These ads are typically between 80% – 150% ACOS which has taken some getting used to. We have seen an increase in out total revenue since running these ad’s and I have managed to keep our total campaign ACOS at about 30%, so I am feeling more comfortable with them.

I know that what I am doing is working, but I am curious if there is a better way to measure our success. Let me know what you think!