tks your adviceOh I don't know much about it tbh, so me giving advice would probably harm your SEO. But I have some advice still. Don't focus much on "on site" SEO, you don't have much to play with unless you add more content. Focus on off site SEO, get your links out there, but do it in a natural matter. Get involved in communities, ghost write well written articles for populare/relevant blogs about you and your competition. The trick is to get people to recommend your service, once people start talking about it it will spread like wildfire. (..and yeah, you need to have something that's better than the thousands of thousands image hosting sites to actually get people talking)
My best tip to you is patience. I'm not a pro or anything but I ranked on first page for "free image hosting" with my previous site "photoland" in about 2 years. With my new site I'm currently ranking second page within a year, and that is probably slow compared to others.
tks your advice+1 on the background image color, the way it fades to the other colors looks great and you chose the right colors. As far as SEO, you have the options to create pages in Chevereto. I know it's not idea, but create some good pages with some good content, text and images to compliment the articles. Make a few posts, should do you some justice in the end. Has for some of my sites.