With a new child, it is often difficult to get out for a night on the town. Try renting a meaningful movie, or planning an elaborate dinner after the little one goes down to sleep. Even a favorite board game would be appreciated.
A good date night in my mind is to watch a movie at home. This could be an old movie that comes from one of your first dates. Your wife will feel special because you remembered something from one of your first dates.
Why not choose a country and base your evening on that? , say you chose England you can cook a typical english meal with english music, watch a english movie together. Add some decor for example flags,the Queens picture. You can travel the world wihout leaving your home!
Go through old photo albums from when the two of you were dating as well as your wedding albums. Talk about the special times and what you were feeling as the pictures were snapped. Share a bottle of wine and some grwon up snacks as you are doing this.