For China Airlines of Taiwan as opposed to Air China of mainland China:
Pay for an F.O. is probably in the $5000/month range. Maybe it's up to $6000 now, but pretty low compared to Vietnam and Korean pay for F.O.s
One good benefit is national health insurance. I know, I've had a kid there and it was good care at a very affordable price. Easy to get in to see doctors for minor issues as well.
Can't help you with the rest.
TP