By the way, this is exacty what we do.
I created a complete windows OS VM, with everything optimized and up-to-date (patches, vm tools), installed the latest proxy version on it, and created both a template and an OVA file. Then I can use guest customization in vcenter and deploy the VM in few minutes, connect it to Veeam console and if meanwhile there is a new version of the proxy, at first login it will be updated automatically by Veeam itself.
EMEA Cloud Architect @ Veeam Software
Veeam VMCE #1