FFMpeg wiki: "For source files of 1080p and 720p av1 optimization is not optimal, most of the time is better to go with the H265 for better vmaf/size ratio"
Here, av1 is 330mb, h265 is 620mb.
I used hardware acceleration for HEVC but I doubt it would make that much difference
@matrix yup. should do better with CRF at similar size fwiw, at least that was the case with x264. CQP cripples rate control.