What to use in 3 clusters and standalon

i want to ask what is the best thing to use for my servers
i will use Grafana for monitoring, i will have 3 clusters servers on each has 3 servers total 9 servers
and i have 5 standalone server as well
i want to monitor them all, should i add one by one to the Grafana or should i use Central Repository will be better ? if so for Central Repository what is the faster method to use for the long run ?

I use Central Repository only for Grafana’s Dashboards.
For other purposes I use the local SQLWATCH databases on remote instances (notifications in telegram for example).

ok great yes i want to use only Grafana now
for cluster server when adding it each server alon right?