I used to have interests involving different cultures, so I would pretend I was someone from that culture. For instance, as a child I was interested in American Indians, and every day, I would pretend to be Indians with my little brother. We had an elaborate imaginary world....actually, it was mostly my world of Indians, he would just follow along. When I was older, I liked ancient Egypt, so I used to pretend I was the pharaoh Ramses the 2nd. I had a friend who was just as obsessed as I was, and she was the pharaoh Thutmose the 3rd. We´d dress up in makeshift pharaoh outfits and talk about Egypt all day, like how the Nile was doing that year or how we just won the war with the Hittites or something....
When I was a young child, my brother and I used to put together little towns; we had all these really nice Swiss toys, blocks that you could make roads out of, train tracks, houses, boats....everything. We would spend days making whole cities in our basement. We invented an imaginary island, and I made up a whole culture and history of that place.
And that brings me to my next point: much of my imaginary play was "in my head". Oh, I would start out with toys and things, but you can only do so much with toys. They are kind of limiting. So whatever I started with toys, I would then go and think further, in my head.....so much of my "imaginative play" later became daydreams in my head.
For instance, I used to have a lot of dolls, and I used to like them, but I don´t remember playing with them as such, at least not so much. I used to be frustrated that dolls were limited, and couldn´t get into many positions. So I imagined my dolls as being like miniature people, and doing all the things they couldn´t really do. I had them lined up on my shelf as part of an imaginary neighborhood- each doll was put in order of where I decided she lived on the street. I decided which dolls were sisters, who was friends with whom, who was crippled, or whatever else took my fancy. Then, rather than really playing with them, I "thought about" them. I guess to any passing observer that would look like "lack of imaginative play".
Then sometimes, I had one favorite doll, which I took everywhere with me. But that meant the doll just basically experienced whatever I experienced. So I guess that bit wasn´t very imaginative. 
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"death is the road to awe"