Art is in fact, subjective, and thus indefinable.
Of all things, art should be pleasing in one way or another to one or more of the senses, and it is that from which you derive your please determines just what pleasure is. To me, scenes of intensity, be it beauty, sadness, lust, joy, bravery, or whatever. If it isn't intense, I am not impressed. From this page, you will see all the art that I have found to be at least a little bit impressive. My very first example of Dwarven Tavern Worthy artwork comes from Kelly J. Foll , why not drop her a line and let her know what you think of her work.