So far so good, i now scrape all the Data via Exporter to Prometheus and can add Graphs to Grafana. i am not really a pro but i will create an initial Dashboard, actual State:
if someone want to contribute, let me know, i think there are more talented guys out here 
Another short Question regarding the numbers. If i want to show capacity vs usage i think i need these values:
- storage_remote_bytes - number of bytes stored on storage nodes (does not take into account the expansion factor of erasure encoding)
- storage_free_capacity_estimate_bytes - statistical estimate of free storage node capacity, with suspicious values removed
Regarding the Description of storage_remote_bytes i need to multiply it with the expansion factor (which is 2.7) to get the real amount of data stored across all nodes, right?