Good work!
Your weight worked out to about 71kg from the math on the AP, I think. Given that and the 227w, something is off on either your road bike position (aero) or your tire CRR. I am always around 70kg plus or minus a bit.
Your ride was 40 feet per mile. Lately around here on the roadie I'm 70kg and 230w AP on 75 feet per mile is getting me right close to 20mph. I'd say maybe your meter is reading high, you have your weight set too low and is actually higher or some combo of aero and tire CRR is holding you back from "more".
I also say analyze your route. Are you losing a lot for coasting down hills or around corners or having to re-accel from lots of stops?
Here's a metric I did recently on less power, same weight, and LOTS more elevation per mile......you've got some efficiencies to gain somewhere.....
https://www.strava.com/activities/5388992061