".....rely heavily on the use of the head voice."
I'm not sure to which countries you are referring in particular - but I'll bet you that their song culture is not a narrative one.
Some years ago a singer friend nearly drove himself (and the rest of us) barmy trying to conquor 'throat singing' as practiced in Mongolia - ie producing sound through the nose and throat at the same time ("because it was there", he told us). According to your logic, if he had succeeded it would be 'natural'. He failed dismally and returned to being the superb singer he has always been.
Male falsetto is certainly not natural but, I understand, the product of hormonal imbalance - or the surgical removal of a certain piece of equipment.
In the end you will sing as you wish to sing just as I will judge your, or anybody's singing according to my own standards, and that is the way it should be.
Even if you decide on head-voice I am in no way convinced that it will make the slightest difference to your range problem.
Good luck with any way you choose.
Jim Carroll