No matter the size of the canvas, creativity is within it's borders... Seriously though, the whole banner design adds a sense of professionalism to all channels and despite the size of the banner I have seen some very creative ways to show off personality within, a example is SSOHPKC's banner which dons more of a NES menu design, it offers the same amount of creativity required for the last design it is just up to us to make it our own... In fact the smaller size in my opinion forces us to utilize the space better and gets rid of people throwing random stuff in the background to make it seem less plain... However, this is just my opinion on the matter.