One way that you can beat the competition is to have a speciality. If every other landscape painter has a variety of landscapes and you do also, it could make it harder for you to compete. If you however, have a speciality, it could give you a competitive advantage. Let's say you specialize in Skyscapes. This doesn't mean that everything has to be a skyscape. But if 1/3 of your exhibit is Skyscapes and they are grouped together, people will start to get the ideas that you are the sky painter. Because you have a lot of sky paintings, you are more likely to sell one, because you are giving the customer more options. As opposed to the other artist who only have 1 or 2 skyscapes. Some people have particular interest, and by doing this you are targeting those people.
Since we were talking about Skyscapes. here is one of mine