First Cdrama was Strange Tales of Tang Dynasty, not sure what first Cfilm was. That was decades ago, same with Japan though that had to have been a Kurosawa. Raise the Red Lantern with Gong Li was when I got serious about finding C-films. First J-series was probably Cherry Magic, first K- was Queen In-Hyun's Man. First Thai was Moonlight Chicken and I haven't looked back.
There is so much Thai free to stream I'm able to find more than enough legally on youtube. Thai PBS is also free to view and has some exceptionally good programming. The only service I'm subscribed to is Channel 3's online streaming. I don't watch enough C- or K- anymore to justify any of the mainstream platforms and I'd rather give a bit of money as directly to the producers as possible.
Really keen on Aom Sushar just now, probably always will be. Perennial favourites are First Kanaphan, Ohm Pawat, Mark Pakin and Ciize Rutricha.
He's Coming to Me and Moonlight Chicken are on my mind a lot right now, so we can call them current favourites. But also Astrophile and Ghost Host Ghost House. And of course Low Season and Enigma, which everyone I've gotten to watch loves too :) Probably simpler to just link you my list.
Don't know if any of this will appeal to you but most of it is readily available in case you want to explore.