Burmese b/f getting k-1 visa to Ida

[SicaHafan]

Hi all,

I live in thailand and my burmese boyfriend of many years is here living with me as well. We are in a legit stable relationship and have a 2 year old son. Our son was born here but recognized as strictly American (like me) because my boyfriend didn't have his papers together (was here illegally) during the time of birth so he's not on the birth certificate. Since then, he has gone back to Burma to get all his papers straight and now has his ID card, so should be able to apply for his burmese passport without problems. He's never been married or other kids or anything, and would re-enter thailand legally on his passport. From there, we'd like to apply for a k-1 fiancé visa so that we can go to the states and get married there and see family- possibly even live there down the line. Our son already has his US passport.

Does anyone have any info to share on the difficulty of this? We've got tons of evidence of our life together over the years, and we also want to look into getting his name added on the birth certificate of our son- I would imagine that would be beneficial during the visa application process to the states as well. He wouldn't be able to prove strong ties here, but is that necessary for k-1 visa anyway? He speaks great english but his reading/writing is spotty, not sure if that's something they'd judge him on, and he's a tattoo artist so has many tattoos- most being Buddhist and coverable by a shirt, and nothing offensive. We shouldn't have any problem proving the legitimacy of our relationship, as we have nothing to hide and plenty of history, but are there other concerns I should think about that could be the cause of a rejection? Anything else I should prepare for in advance?

Any info would be greatly appreciated. Thanks for your time.