JP White,
I would probably still be driving the 2011 and would have mileage similar to yours if it had not met an early end. It had several features I liked that the 2015 did not have and it had more insulation (for both sound and heat) than the 2015. The 2015 had a few features I never really learned to like (foot pedal parking brake and black leather interior, among others), but I might have decided to replace the battery and keep it if Nissan had not introduced the Plus model with twice the horsepower, much larger battery, and better battery warranty. The 2019 has light gray leather interior, electric parking brake, and better insulation so it has most of the 2011 features I missed. I still miss the power-adjustable headlights, but that is a minor issue.
I hope you get many more years of use from your 2011.