For enhanced safety, it would be good to have a possibility to block strange/unknown/evil DHCP servers on the network. E.g. when someone else attaches a device on the network and runs a DHCP server, intentionally or by accident, all users on the network might end up in trouble.
Having a functionality on all managed switches and the LAN-side of the MAX routers to only allow known DHCP servers (or only the internal one of the Peplink device) and block all DHCP offers from other DHCP servers, would avoid this kind of misery. I always use that functionality on Meraki switches.