prometheus and grafana … seems to be the universally accepted solution for self-hosted monitoring

Not exactly. There are many ways to do this. Most of us just use this solution because its easily scalable, highly documented and what we are probably already doing currently at work.

all built into one container

It’s nice to separate data sources from the dashboards and alerting platforms. It’s scalable and extremely light weight and gives you more options.

On top of prometheus not seeming useful on its own …

Yeah, that’s just not always true. Maybe for you, in your use case.

Installing a Prometheus node exporter gives you an easily accessible end point with JSON data that can be used however you like. Modularity is a good thing. Being able to swap parts in and out with other parts is a good thing.

If you haven’t figured it out yet, there is not an exact correct answer here, use what fits your needs. While I have a dash board setup in grafana, it’s not my main use case. Since the data is available from all the node-exporters on all my hardware, I wrote up my own alerting scripts and automations using python.

That’s the beauty of modularity and standards when self hosting.