I would say that both JP and non-JP version has their own poop that's hidden from first-glance basis.

As someone who still play both version; I'd say that community-wise, JP and non-JP are not much different from each other, contrary to what people in general thought about the community. It's just that SEA had this disadvantage of having AS as it's regional publisher.........which is 'unofficially' dubbed as the worst publisher in SEA......except for TH. TW had a better publisher, and I can see why people there are willing to throw lots of money for AC.

In any case, people are free to play at which region they prefer. Going to JP? Go ahead. SEA/TH/TW? Sure, why not.
Just make sure to read the comparison between those servers with a grain of salt, and make the decision yourself.

And this thread derailed into JP vs SEA in a record time. Wow.