Re: priorize vpn traffic?
What software version do you use? Every version have many new features 5.6 vs 6.0 vs 6.2.0 s 6.2.1.
How many WAN links do you have? If more than one I'd try to separate VPN traffic from the Internet, I think you could use PBR.
Is there any reason you can't add WAN dedicated for VPN to the SD-WAN? By creating rules you can totally separate traffic between two or or more groups of interfaces.