Using emissive materials, I forgot to look at how long it took, I think I ran it for 40 minutes-ish, same scene settings as below.

Got my microfacet material working again, and the return of normal maps. About 15 minutes.

Fixed everything, this is using progressive rendering, doing 6 samples at a time. About 4 minutes

Fixed some brightness issues. I let this one run for about 5 minutes

Multiple Importance Sampling with the power heuristic, took about 20 seconds. Im getting a lot of fireflies, and the noise takes a while to resolve. Still dont have roughness either

Pure Vanilla Path Tracing ran for 6 hours with progressive rendering for reference. I havent done roughness yet