Neither the Asia Pass nor the China Pass are a good idea at all for the OP (or generally for anyone ever). They just aren't good products.

From a SkyTeam program perspective there isn't a great amount of coverage in SE Asia. China Southern has some flights. NW has a small hub at NRT, but that is limited, too. And there are a couple one-off flights from KQ and AF, too, but really not many.

As for a program to join, I'd look at the EVA program. They are going to be your best bet for flights in the region since they are the main carrier out of TPE.