I saw this ad on the side just now (it was an ebay ad for the pattern)....I LOVE the cheese/mouse combo! I would have never thought of incorporating the stroller into the costume.
That is cute! A lot of people in the city incorporated wagons into costumes. I remember seeing a toddler dressed as Ariel and they put cardboard waves around the wagon. And another little boy was a scarecrow and they had a little bales of hay and cornstalks decorating the wagon.