i don't know what is "the best, RightWay,.." ke-recv or udev rules.
now, i use for myself an udev rule for automount. because i am lazy* the rule point to a custom variant of original h-e-n mount routine and my actual host script ( v2, not public yet ) don't have any mount call.
for same ( * ) reason cdrom rule ( sr* ) is missing
it look like
saved in /etc/udev/rules.d directory as 94-automount.rules
"run" section can be modified to point mmount program and above rule is a start point for what the rule should be.
i prefer this because it's easy to be modified

I propose that the ke-recv to handle battery charging, usb type detection is there and boost check also can be, to trigger charging mode.