Definitely far too unique of a case for general FB advice to be of any value to you. Seek some professional advice as suggested, and honestly if you can't afford that then i would seriously rethink your next steps
AIS is fine, i have a post paid business plan with them and my family have prepaid "tourist" sims, both have very fast speeds on 4 and 5g. I have a teenager so i would know all about it if it was slow
Bangkok and kasikorn both good for wise, many others have a cap on how much you can send per transaction. I have an account with both and they are both good. Bangkok bank app is nice and easy