I feel all the old paintings are part of what gives SDC its charm and what sets it apart from other parks. My favorites would be the Kieffer paintings at FITH and outside the Ozark Marketplace. The ticket booth painting has a special place in my heart, too. As a kid they always gave me a little bit of a scared feeling, but in a good way. (Hard to explain really, but I would surely miss them if they were gone).
I would LOVE a coffee table book of all the art work across the park. The George Kieffer stuff especially, but the others as well. [Seriously, TPTB, if you are reading this, I would buy one in a heartbeat!]