Im not sure im skilled enough to give critique when there is others doing it better. But, what they mean by messy composion on the second is that there is a lot of vegetation in the foreground that makes it messy. If you dont have a tripod, you have a good steel fence with the snails on. Use that to lean your camera against and go for some close ups. Snails are sometimes tricky and its hard to get both eyes in focus, often the move their eyes in, in that case, just wait a few seconds and they will surely pop out again.