I have been living and working here for the past 14 years using a Non Imm B with annual extensions and a work permit.
Just wanted to update that I came back to Thailand last Thursday through Suvarnabumhi about 11.30am using a re-entry permit. No conversation with IO about anything.... Money, flight, accomodation etc. No fingerprints but did take a photo. Stamped in until Feb 2020. Queue was less than 30 minutes. So the experience was exactly the same as it has been for the last 15 years.
TLDR : Answer Summary
The user shares their recent experience of re-entering Thailand after 14 years of living and working there on a Non Immigrant B visa with annual extensions. They noted a smooth process at Suvarnabhumi Airport with no inquiries from immigration officers, using a re-entry permit, and a quick queue.