a movie,park,picnic and decorate the house romantic by bringing the outdoors inside and doing a picnic,resteraunt,skating or ice skating,bake cookies or cook together,drive in movie theater,candy shop place,carriage ride,go to a musical,concert,a baseball game or a basketball game,art lessons,play video games like gutiar hero against each other or something,go carting,david busters has games, food and i think also go carting.
This is what I would do. I would take my honeymoon out for a fancy dinner. If you want to impress him/her, take him/her somewhere that's expensive. If you can't afford it, Take him/her out to the pool. And when she/he is comfortable in his/her bathing suit, get sexy. Play around with him/her stuff.
OTHER IDEAS: Go to a Movie Take him/her to a Concert Go to the beach Romantic Walk Go to the Mall Go to the Library
Winter: Skating! That would be so adorable! Also take her to a nice cozy cafe after that. Summer: Bike riding, Blindfolded dinner at a green space, Go to a mountain and sit there with her looking over.