So I followed the advice I got through this thread. I modified my covers, I've set up a free promotion that starts tomorrow, I've started writing books that begin a bit more sexually and I'm going to cut out on the superfluous stuff. I just released my latest book, but I had written 80% of it before starting this thread, so it doesn't have all the new additions in it.
My next book, I've cut down from the planned 12,000 words to 4,000. It's a challenge to write short fiction like this, but I'm embracing the challenge. But, if I get the hang of it, then I'll be able to put out work quicker, so there's that. And, if that's what the audience is looking for, then that's important too. I'm still going to do the odd longer piece but I think my next 5 will at least be shorter fiction, and I will see how they perform against my longer ones.
Any additional advice is welcome, as I'm still only selling 1-2 copies of each book (with the exception of one, which sold a few more). I'm remaining persistant.