A hybrid power train takes a little getting used to, that's for sure. I think you are on the right track taking the eco off when driving in traffic. The Insight is my wife's daily driver, but whenever I drive it such conditions I also shift to S. That keeps it from doing auto stop which I find essential just to keep the A/C going.
Here is something you can try to help with the jerk in the AM, something I have been doing with all my automatic trans cars for years. When parking, shift to N, set the parking brake, take your foot off the brake pedal allowing the car to come to rest on the parking brake. Then shift to Park. The next time you go to shift out of park it will be like butter.
Something else that I thought of while typing all this is that your independent mechanic says the trans fluid looked like it had never been changed. That might indicate that your Insight had never been back to a Honda dealer since new. 2010 & early 2011 Insights have software updates available. There are three or four and a couple of them specifically address your complaints. Read through software update threads here for specifics.
Last edited by egads; 01-25-2017 at 11:57 AM.