Ecommerce Metrics to focus on for Reporting (Revenue vs Transactions vs others?)

Hello fellow SEO's

I was looking at my datastudio reporting this morning and I deciding to explore a bit more about what would be more important to look at, or if certain metrics should be singled out.

I work on retail e-commerce domains and I usually looked at sessions vs revenue

What im thinking about is if revenue is a true reflection of an e-commerce stores success since there are so many variables or not. Im specifically talking about how revenue could dip and grow because of sales,trends hitting or in one month 2 large price items were sold,etc etc

So im wondering if its best to keep an eye on transactions rather (ruled out conversion rate because if the data size decreased then 1% CR "look" healthy until you dove into sessions and discovered that the 1% could swing for a 1000 or 10,000 people (sigh percentages and averages are a mess if you don't know how they can mess up your data)

Any thoughts? For now im creating a two axis Session and Revenue for the client, just feel there could be a different setup.