That's my current configuration, it works well. Put your storage on a separate network. I use smb shares so my data is password protected, even on that separate network.
Main downside of this is there's more places for failure to occur. If your NAS goes down, there's no storage access for proxmox which may cause service downtime. Alternatively if proxmox goes down, this also causes service downtime. For me this is fine, but something to keep in mind. Ideal solution would be 2 HA clusters for storage and compute, but thats expensive haha.