Jurgen - I'm not nearly as experienced as rtsjr when it comes to mixing.
I can tell you though from recent experiments cutting with all PG is rather harsh on the throat and makes a good ghost vape. (almost no smoke & very, very "dry")
I haven't quite figured out my PG/VG ratio yet but I'm close. Make small batches until you get it sorted out...your throat will thank you for it.
That's all I have...
I will try to figure it out. Everybody has to find his own way. But I am very comfortable so far, because I did not light up since Christmas last year....Thanks again.