They are aesthetically pleasing to me. I might even hang some prints on a wall, but it would be to add some color, not because I find them to be a superior disp

They are aesthetically pleasing to me. I might even hang some prints on a wall, but it would be to add some color, not because I find them to be a superior display of artistic ability. To be fair a lot of simple looking art like this is produced by artists with a sound understanding of composition and color theory. For some of them everything they do is done with intention and thought. However, having a sound understanding of color theory and composition are just two basic skills any good artist will possess in addition to a multitude of other skills. Note that I'm not saying that artists have to adhere to standard color theory and composition. I'm saying that when people deviate from them usually the good ones do it in an intentional way with a full understanding, and the specific way they break the rules is well thought out and so it works.