I dabbled with QUIC a few years ago and I couldn't agree more. It was pleasant to work with, and because it's UDP based, suddenly you can do NAT hole punching more easily.
Funny that you mentioned a VPN, because I made a little experimental project back then to hole-punch between two behind-the-NAT machines and deliver traffic between them over QUIC. I was able to make my own L2 and L3 bridges across the WAN, or just port forward from one natted endpoint to an endpoint behind a different NAT.
At one point I used it to L2-bridge my company's network (10.x) to my home network (192.168.x), and I was able to ping my home server from the bridging host, even though it was different networks, because it was essentially just connecting a cable between the networks. It was quite fun.
Funny that you mentioned a VPN, because I made a little experimental project back then to hole-punch between two behind-the-NAT machines and deliver traffic between them over QUIC. I was able to make my own L2 and L3 bridges across the WAN, or just port forward from one natted endpoint to an endpoint behind a different NAT.
At one point I used it to L2-bridge my company's network (10.x) to my home network (192.168.x), and I was able to ping my home server from the bridging host, even though it was different networks, because it was essentially just connecting a cable between the networks. It was quite fun.
Here's the project if anyone is interested: https://github.com/binwiederhier/natter -- it's probably defunct, but it was only experimental anyway.