I had this Arc for 7 months now but it is linked to a Chinese course I was taking at one university. It’s a student arc so I’m not allowed to work legally but a man has to do what he has to do so I’m doing something on the side. I just plan on staying here for another 3 months, and maybe come back later when I have more time.
I’d just search on Skyscanner with the “everywhere” option and see what looks interesting to you. Though, after 2.5 years of plague restrictions, the feature doesn’t seem to be working as well as it used to for the dates I just put in - maybe you could try Google Flights or whatever instead.
I wouldn’t choose Okinawa personally, but you’d have to check what’s available and the flight prices (and the cost of being there also). I assume (not sure) that HK is still out, but there’s still Thailand as you said, the Philippines, maybe Malaysia, Korea, etc.
It’s probably a bit more expensive than it used to be.
Philippines is pretty cheap now that Cebu Pacific is up and running again. The other usual options for visa runs are a lot more expensive or have major downsides (eg., HK).