How about not making any plans at all? Go with the flow! Take out your car, just pick a direction and start driving out of the city. You both can stop at a dhaba, explore some new places, or get cosy at deserted highway roads. But make sure, you have filled the petrol tank to the full.
Now, that you know how to re-kindle romance in your married life, just, roll down the windows of your life and let the fresh air of love come in.