What backend metrics system do you use in 2021?

Hello, Indie Hackers!

My app is starting to get a ton of users using it very quickly and I am currently using raw logs from Heroku to track usage but there isn't enough to know what my users are doing on my app.

An example is that sometimes I deal with Stripe payment disputes from my users and have no records to fight against it.

Is there a bootstrapper friendly metrics system that collects this sort of information?

If you roll your own system for this, how did you do it and what do you use?

Thanks.