Welcome to PRIUSchat!! You will LOVE your 2014 Prius ..... your not killing it!! Their are many good tips here; you can pulse and glide; coasting; anything over 7 MPH in " D " helps charge the battery; if you do it right, you can get GREAT MPG. Put the A/C in auto, sometimes you can turn it off; if it starts to get HOT again, just turn the A/C back on again. This might also help you: Better Gas Mileage in a Toyota Prius - HybridCars.com
Also as a newbie, make sure you're using fuelly.com to keep track of mileage. I kept track on every tank of my 2010, now starting up on my 2014 (one tank so far). Really helps see how your car is doing! I use the mobile website on my iPhone but they have an app as well... I had been using the mobile website since before the app so never switched.
No worries. The Prius is perfect for you. I contend with similar traffic during my weekday 1 to 2 hour commutes home, from work in grid lock, crawling from a stop and go traffic on the freeway. Using ECO mode this afternoon, I achieved 80.1 MPG; surpassing my last at 79.8 MPG. Incredible!. My early morning 30 minute commutes to work are much easier, since I start work at 0700; avoiding traffic. This morning, 52.4 MPG. My lowest ever was 46.5 MPG; while running late for work in Power mode, flying on the freeway at 70-80 MPH with no traffic. Overall I'm averaging 58 MPG toggling between ECO, EV and Power modes. I hope you enjoy your Prius as much as I do mine.