The bulk of your AHI is central in nature (CAs equal central apneas).
More pressure isn't the fix for centrals.
You might want to learn how to distinguish awake/arousal related flagged events from asleep events.
I am betting a good chuck of your CAs are arousal/awake related.
If you aren't asleep they don't count other than pointing to not optimal sleep quality with the arousal breathing.
Watch all the videos here.
http://freecpapadvice.com/sleepyhead-free-software
You could maybe try reducing or turning off EPR to see if the centrals reduce or you sleep better or not or you feel more rested or not.
Sometimes using EPR exhale relief causes centrals....I seriously doubt it in your case but it's worth investigating and a quick easy experiment to try just to see what happens.
6 hours isn't enough sleep to expect to feel very much better more most people.
Maybe you simply need more sleep overall......I know I feel like crap if I get less than 7 1/2 hours.
I may have to RISE but I refuse to SHINE.