There a few tools like Pluralsight Flow and Code Climate that focus on git specific metrics (e.g., time to merge, developer velocity, etc.)
On the ops side of things, if it's a bunch of repos feeding into a larger service, you may want to look at a service catalog offering. This kind of tooling shows what's running in production, who owns it, and how healthy it is. Open source offerings are Backstage (by Spotify) and Clutch (by Lyft). There are also SaaS options available like OpsLevel.
(Disclosure / Shameless Plug: I'm CTO/co-founder @ OpsLevel).
https://github.com/joecummings/gitmine
It's open-sourced so if it doesn't exactly fit your needs, just open an issue and we'll look into adding to it (or you can submit a PR yourself).