Given the enormous scope of the question, the US west coast almost
sounds like an effective common denominator *regardless* of the
state of interconnection within the region, or the history of
US-centric traffic demand and under-sea cable routes.
PAIX alone can supply 10-15k of AP routes, coupled with AP routes from
ABOV and others, that would be most it.
No matter where you are located in AP, its going to be a long and
difficult build to get a similar level of routes from within the region.
Now if you coming from Europe it would make even less sense.