The main complaint is: it's a bit ridiculous to think of civilizations rising and falling because of tourism. Tourism, really, is just a particular commercial activity, a luxury consumption good. It didn't motivate the rush of archaeologists, the composition of operas, the production of literature. It didn't cause the collapse of communism or fascism, or rebellions and protest movements. It's roughly 5% of global GDP, in today's global world where jet travel is available to the rich country middle class (and the Chinese and Indian upper middle class), and was likely much less than that in the past. Basically: tourism just feels, well, small. It makes more sense to think of "influence" or "prestige" - or "culture", of course - as being the big ideological influencing factors. Once you know what you're looking for ideas on, it might be worth creating BNW threads for brainstorming ideas, which include the GEM designs as a source of comparison/inspiration.