Heh well there are different ways to be imaginative.
I grew up with a sister two years older than me who was able to correct me when I would put cowboys in cars, give knights guns and other such things. So we did stay pretty historic, but more an idealised version of it.
Originally Henry, Roderick and Frederick where each a prince of a different kingdom for example, but somehow they where usually with Roderick. There was no swan or tower king after all, but I did have King Phillip. They'd hunt, fight in tournaments, pull pranks around the castle.. basicly it was somewhat like many cartoons set in medieval times and also comics. But even then we did want to make our own characters. We never copied people directly, sometimes an event that seemed interesting yes, but our characters would respond in their own way to it.
I'm pretty sure you played with your victorian house also in ways that when you think back at it was not realistic. But being able to play on your own and be able to create your own stories that may be inspired by what you saw elsewhere but is not a direct copy, that is using your imagination to me.