We don't have enough information yet, we just know that whatever we find, no matter the explanation, is going to change our understanding in a big way.
you hit on this in the middle of your post and really that was my entire point. I think we agree, mostly. My main point was that growing up I was taught in school that the first civilization was the Sumerians which ran from 5900-2900 B.C. This find at Gobekli predates the Sumerians by 4,000-6,000 years. That is insane. Think of this mind fuckery. The Sumerians of 3,000 B.C. are closer to you and I than they are the people who built Gobekli Tepi.
Regardless if they were hunter gatherers, which I have a hard time believing, or a legit in place civilization, or something in between, I think Gobekli basically ends up rewriting the text books on this topic. As far as how basic the carvings are, I don't think you may end up being right about their rudimentary nature. Those carvings are base relief, meaning the entire stone has to be carved away to leave the art raised. Craftsman, expert stone masons of the time would had to have spent a huge amount of time on it because of the sheer number and size of the stones.
Look at these and picture a guy from 12,000 years ago using a homemade hammer and chisel to do it.
Look at the work here done even along the bottom on the base that the pillar sits on.
A size comparison to a human so we know what size stones we are dealing with here.
Each pillar* has a height of up to 6 m (20 ft) and a weight of up to 10 tons.
The entire complex is rather large with at least 200 such pillars. Then you have the mystery of why and how they buried the entire site under sand. How and why would they do such a thing is a mystery but it would take a HUGE amount of work. I don't think we are that far apart on opinion here. The site is an amazing and groundbreaking find.