[Aaron]

Perhaps the literary function of Bombadil was, in fact, entirely dependant on the reader's own perceptions of him - and, by extension, nature.
Readers with a romanticised view of the natural elements, and the simplicity of it all, would see a benevolent fellow peacefully removed from the materialism of the other world. But, for people like myself, raised on dark stories of ghosts and Witches and evil spirits, he could be perceived as a malignant entity - representative of nature's bitterness at the world of humanity, and its careless whimsy in the face of human order and structure.

The question of 'perception' could then be said to tie into Tolkien's own love for nature, in regards to both the beauty of it, and the menace lurking beneath the surface - allowing his readers to colour Bombadil however they saw fit, in the same way that a Woodland by sunlight may be peaceful, but at night frighten the unwary traveller with far-off rustles and shrieks.