I think you are improving. Dark backgrounds are really tough though. All the little specks that you couldn't see with the naked eye when you were setting up the shot pop out in the finished photo.
You might consider keeping a soft brush handy to do a cleanup around the subject just before taking the shot. Alternatively you can use photo editing software to eliminate them or blur the background to make them "invisible". But some people frown on photoshopping for things like contest entries. With the bash coming, this is something to keep in mind.
Ed