Splitting AFC wont happen ever.
1) West has money, But no where near the money coming to FIFA and the AFC then East. As east really has more money tided into the game(TV rights/sponcership/supporters) , And way more growth then the west nations period.
2) West is 9 nations at most, If there was a spilt you would find country's like Lebanon and Uzbekistan joining UFEA as offered a few years back.
OFC will not merge, It would lose to much money and being governed to meet the AFC criteria means the island nations would just fold as there used to getting some lead way from OFC.
So New Zealand should go it alone? Well the Muppet's running the ASB prem would LOSE any right to play in the ACL as its for Pro clubs only. ASB prem sides would not play in the AFC cup (the poor nations champions league) as they (New Zealand) would have a team playing in the A-League.
NZF would be governed (for once) and would have to take some big steps to meet what's needed for world cup qualifying placings etc etc.
Women's game would just go into overdrive both on and off the pitch.
PNG wanted to join the AFC (Or the elected board at the time) but was over-throne and banned back in 1998, Solomon Islands where invited to join ASEA (then later join/become a AFC member) but turned it down in 2007.