What I have found really useful is the following strategy:
For tracing projects, we only use:
- Production
- Staging
However, to divide the individual traces with an isolated unit for Team or Project, we are using metadata tags, e.g., “project_name:xyz”.
We do this as this allows for easy filtering and allows full visibility across different team/projects (but be mindful I am part of a small startup, so in a big organisation this might be different).
For my other Mental Model about evaluation, I have already given a comprehensive answer in this thread