If you live in Chiang Mai I would definitely open my bank account there rather than somewhere cheaper or easier. There are a variety of good reasons for this, chief of which if you need to do something official, you will be asked to do it at the branch where you opened the account.
Perhaps you could include some links to articles discussing this Thailand banking corruption / risk of loss of deposited funds you are so worried about?
I’ve personally never seen or experienced anything to give me the slightest concern over the money I entrust to Thai banks. I actually feel it’s safer there than in a USA bank.