HDlight is like MiniHD, just a way to mean HD quality with light weight, but with special algorythm so that the compression is not noticeable.
4.1 is just a profile in Handbrake (follow instructions in the french tutorial. even if you dont understand the language, you should manage with the pictures). To achieve max quality you have to set "2-passes" in HandBrake (the 1st one can be set to "fast" though), and you have to copy-paste the special lines in advanced tab.
With these settings I manage to have multi languages movies in crystal-clear quality for about 1.6 Gb (720p) or about 3Gb (1080p).
I compress in MKV, x264, AAC (yeah I know AC3 would be better, but AAC is compatible with more devices)
But be warned. "Light" HD profile when set correctly gives really incredible results, with smooth gradients even in dark or fast paced scenes, but it requires
TIME and
POWER!
I gave up compressing on my MacBook Pro at home, the CPU was at 1000%, the fans were screaming, the battery yelling and took more than 10 hours for a fullHD movie.
But at work I have a 2012 MacPro very very powerful, and I compress there the movie while I work on usual daily design projects. At full quality, 2 passes, a 1080p FullHD of 90min takes about 4 hours to be compressed, a 720p HD about 2 hours.
The new version of Handbrake have beta support of x265.
But I advice you to not use x265 for now:
1) the standard is not defined, still in discussion so you may have compatibility issues with devices later.
2) no hardware acceleration in Kodi