As I recall you stated earlier you have not ridden much in years. You will get faster as your body relearns to develop power in circles. I always suggest to ride for 20 minutes or less and get off the bike. Don't do long rides until your body starts to adapt to riding again.
Your fitness level will come up quickly and even if that doesn't change much you will be able to power bike much better with regular time in the saddle.
Enjoy your new bike. You made a good choice.