I find that I enjoy using images, and if they are well-chosen they can enhance a story. However, I think it's important not to rely on pictures; the story should be written such that the reader could follow and enjoy it if the pics weren't there.
They've also helped me in writing. For example, the story I've been working on most is "It's Good to be the King" and I have included a great many pictures. For this story, I had to use pictures with a medieval theme (not truly realistic, as the women have shaved legs and are all wearing makeup even if they're of the peasant class and not nobility, but I didn't care to search the internet for accurate pictures of women from the 1400s!). This narrowed the field a lot when it came to what I had to choose from, and as a result I had to model my characters accordingly. I admit that, left to my own devices, I would tend to describe women as almost exclusively voluptuous with curvy figures and generous busts, but that wouldn't match the photos so I was forced to be a little more diverse!
I also got some story ideas from them. One picture set included a woman who engaged in sword combat, and of course I just had to include that one, and the result was a very powerful scene which I likely wouldn't have come up with on my own. That same model also featured in a picture set where she was imprisoned in a dungeon, and once again it seemed a waste of good material not to use it. This also produced a scene I normally wouldn't have written.
Finally, I find that it's helped me to improve my Photoshop skills. I had one place where I had to show the woman
crying a single tear, as it was important to the story but of course such a picture wasn't available, so I added a tear to an existing photo. I also had to make use of a another picture where I actually had to have the model
clothed rather than partly nude (that one's not very convincing once one knows that it's altered, but I think it looks good enough in passing). Some which were rather fun were pictures meant to represent dreams or visions, and for those I stacked up filters and brushed backgrounds until I found the right
surreal quality.
In the end, the story matters a lot more than the illustrations. A bad story with good pictures is still a bad story.