Tony, the problem you described with Google's image search has something to do how you publish your photos. I tried to find out what the exact file name of your pictures is but failed. It seems to be either some cryptic alpha-numeric code or a strange .png file. Hard to tell... It's the same for Google. It searches for descritions of the motif but can't anlysis yet what the image shows.
What will help is adding some proper discription in the ALT tag and name the files with real words (e.g. Istanblue_blue_mosque.jpg). For more information see this link: http://www.shopify.com/blog/7412852-10-must-know-image-optimization-tips
. Saving all pictutres in the same folder on the server or in easy to find folders (not some generic endless number), will help also.
When I type my name and the name of one of my motifs into the google image search, my photo is the first or second thumbnail it shows, although some where uploaded just a few days ago. A few other photos of my website are loaded among the first ten photos, too. So image SEO really works. But I forgot to give one image a proper title, ALT text and description and as a consequence google does not show it at all in the image search, although it was uploaded to my website 2 months ago.
With Wordpress it is very easy to describe your photos in a search engine friendly way. But it should not be the only reason to change.
Best regards, Robert