I am encoding various video files into H.265 to reduce it's size on my hdd. It's different formats of files and various resolutions/bitrate. With some i wan't close quality to original, with others i can drasticaly lower the quality and live with it. I would like to find the best way to store those files using HandBrake. Right now this is how i lower the size of files, encoding into H.265:
1) I set the resolution: i either leave it at original or i lower it, for instance from 1080p -> 720p, etc.
2) I leave fps at original and set variable fps
3) i set video codec to H.265 10-bit
4) i set encoder preset to Fast
5) depending on the quality i wan't the video to be, i set 22, 25 or 28 RF constant quality
Questions:

1) I have been wondering many times about what is better: resolution or bitrate ? For instance, is it better to set resolution to 1080p and live with lower bitrate, or set it to 720p and have higher bitrate for same file size ? What will give me better image quality ? My screen is 1080p but i never watch video full screen, usualy looking at it at only half the size. I will give you an example:
I did a test encoding of very short video clip. Setting 22 RF got me average bitrate of 1443 kb/s at 1280x720. So i am wondering, would i get better quality at same file size if i used lower resolution but a lower RF of like 18 ..
Also another short clip i did was 28 RF and 600 kb/s average bitrate at 1280x720. Would it make sense to lower the resolution at such low bitrate and set RF to 18 ?
2) Could you point me into a direction to get some extra tips and tricks to get the best quality per size of file, i know certain advanced options can be manualy typed in but i am completely new in this teritory. I will do the reading, just point me in the right direction.
HandBrake version:
I am using HandBrake 1.3.3
Operating system and PC:
Windows 8.1 x64, i5 2500K @4.0, 12GB DDR3 ram, R9 390