FWIW if you want to tinker on the topic I recommend OQS https://github.com/open-quantum-safe/ including Chromium, Apache, nginx, curl, etc. It's quite fun to play with.

What are appropriate default parameters?

The mozilla SSL Config Generator doesn't yet support PQ; it has Old, Intermediate, and Modern: https://ssl-config.mozilla.org/

mozilla/ssl-config-generator: https://github.com/mozilla/ssl-config-generator

"Chrome switching to NIST-approved ML-KEM quantum encryption" (2024) https://news.ycombinator.com/item?id=42265927

"ML-KEM Mythbusting" (2025) https://news.ycombinator.com/item?id=46074381 re: AuthKEM