Well, but I didn't ask for "changes between v6 and v4", I was asking for changes other than the change in address size that hinder adoption--with the point bein

Well, but I didn't ask for "changes between v6 and v4", I was asking for changes other than the change in address size that hinder adoption--with the point being that most of the stuff that people complain about is actually an unavoidable consequence of the change in address size, such as the replacement of ARP with a new protocol that can actually transport longer addresses than 32 bits (and that otherwise isn't all that different from ARP).