Hey how's it going? Nice to meet you. I am sure there is nothing inherently wrong with not using sand, however, it is a very important link in the biological chain. It aids in the filtration of the tank and as you mentioned the overall look of the tank would be strange. There are several types of substrate that you can use still giving the benefit of the average sand. My preference is for the Fiji pink, however there is crushed coral which I have never used but have heard that there are many potential problems with it. Sand comes in several textures and also comes in black. I have even heard of people switching to standard Home Depot play sand. I am sure you can find something pleasing to the eye and will complement the filtration of your bio load. As far as keeping it clean I am a firm believer in keeping my hands off of the substrate. There are pre packaged clean up crews that do a very good job of moving the substrate and cleaning up all of the detritus and fish waste. Sea stars do an excellent job of this as they move under the sand and through it. of course you may still have algae blooms, so ensure that your clean up crew is sized appropriatley for your set up and that they are compatible with your tank mates. Also your choice of lighting will dictate how it is viewed.
Hope that helps, just keep in mind i am by no means an expert just lucky!