PS4 has been updated to work with USB drives and MKVs. Note: they haven't added the ability to select audio tracks yet, so you probably shouldn't include more than one. Also, as it's a Sony system and not Microsoft, they don't support NTFS. So make sure to use FATx for large files.
As for burning the ABCHDs to blu-ray: I think you can do that? I'm pretty sure that's what some people have been doing with Harmy's RoTJ 1.0 while they wait for the next version.