I own a WISP with about 100 clients and admin another wisp/fisp with around 500 clients.
I love "the dude" by mikrotik. It pulls data via SNMP and gives me a great heads up overview of everything. it also graphs the data over time.
I use LibreMNS also to pull network data via SNMP and it graphs historical data.
someone posted this a bit earlier today i think.
https://github.com/horahoradev/PrometheusTube