We have talked a little about imagination before, see this thread:
But I think it is worth seeing if we can add more detail to this topic.
In a way I feel that being a highly imaginative person is a hindrance in spiritual development. Imagination gives shape to desire and fear, positing all kinds of what-if scenarios, and so amplifies their effects. Its flightiness is an opposite of equanimity, so as you develop equanimity you should find imagination decreases.