Jeff,
Yes, I've been able to PRODUCE a 1920x1080 60p with hardware acceleration, then use that file in a new project to burn a BluRay at 1080 60p without acceleration. It burns really fast and I get a great picture. So thanks for that tip, looks a lot better than 1080i.
I've been figuring out my new workflow since I started using a new Panasonic AG-DVX200 4k camera. I get 3840x2160 at 60fps, which looks amazing on my 32" 4K monitor. I use Handbrake to generate 1080 for uploading to HUDL (high school sports video exchange) and to use for editing in PD15. Then substitute the same named 3840 clips back into the project folder and reopen the project. Produce m2ts at 1080p............then burn to BluRay 1080p.
I'm not sure if I'm getting 4:4:4 1080p from my 4:2:0 4K but it really does look sharper/better than standard 4:2:0 1080p.
Now I've burned enough BluRay mistakes that I have a working system, only thing missing is background music during menu selection. It's a nice touch I like but not a gamestopper.
Learned another aspect in all this when I upload highlights/recruiting videos to YOUTUBE in 4K. Within an hour or so, it is available as 1080p. BUT it takes another 3-4 DAYS to see it in 2160p (4K).
Again, thanks for your insight!