I have basically lived in Thailand for the past 15 months except for 3 times I went back to America for around 30 days. I've never had a problem with Visa on arrival or getting a 30 day extension. I have always stayed within the rules including doing a border bounce when needed. I just got married to a wonderful Thai woman so now I'm working on a marriage Visa
If you need any more info DM me and I will try and help