I recommended sketchmob.com (I got all my cover from there). Just pay attention to the review (you can browse the artist's previous works) and read the artist's term and condition if you want to use it for cover.
I saw your story yesterday and also think 'eh? Is that summoner journey's cover?'. Maybe some of them thinking you want to do plagiarism then give you 1*(only my guess). But if you bought the cover just report it to Tony.
I wonder if I'm the only one who like to write detailed fight scene. At my last novel I write about hand to hand fight. When the other combination of sword and magic fight. There's some conversations and thought between it to keep the story flowing or you can add the other reaction or effect...