In todays world, you can have the best keyword list in the world and you will not be ranked No1 until you cough up some money to pay search engines to advertise your site.
Then your other issue is how are your current visitors arriving and if it is a search engine returning your site in the results, these visitors may not see your site as offering them the answer that they are looking for.
If your site is having traffic driven to it, the bailout rate is an indication that those people are not interested in what you have to offer and may have been brought to your site under false pretences or just that these visitors are expecting image editing and image manipulation software and not what you are offering.
IMHO you should have considered a different domain name that doesn't clash with image software and tools, there's many corporations that have domain names that are unrelated to their business / trading name, for example, for obvious reasons, the children's toy shop trading as "The Entertainer" have a domain called thetoyshop.com and that is to stop confusion and eliminate film listings for the film "The entertainer".
Maybe time for a re-brand...