i'm surprised that my preference for side hung doors surprises you ! after all, the majority of doors throughout my life have been hung this way, and they all worked great !
why would you need to leave a door open? and on double cranked hinges, the door opens 180 degrees ,so no danger of nasty edges there .
as for the stiles, not sure why you say they are often narrow - i can make them any size i want, and if the doors are sized to suit the proportions, then the hinges positioning works fine
i do find that an awful lot of self builds are attempting to copy the factory builds, but i also get to see lots of self builds done by young people who just need a van that works, cheap ! and because they have no training they often come up with very innovative ways of solving problems