Routing LAN FreePBX and VoIP phones

It’s just a quick discussion and verification.

in my case, I have a more then capable cisco router and cisco switches handling the package tagging and routing.
Does having the FreePBX server have any decremented impact on overall performance being on separate network then the VoIP phone.
I also currently have the EPM module, which does a good job of provisioning and DHCP services showing where the server is to the phones.

The system is setup currently in production, just wanted to confirm keep this or switching to a flat network with server on same segment as the phones would be beneficial.