(Before anyone chastises me about rushing)

When will the next towns be released? After destroying some weapons, I think I should just wait until higher-level weapons are released. This month, next month, next year?

I wouldn't bet on there being a steady stream, going by Cosmic Break I think we can expect a healthy amount of... cash shop updates but relatively little in the way of actual new content.

At the very least we can expect is the content being translated over from jp version but other than that, they'll probably start sticking to cash shop stuff and "improvements".