To get more microstates I feel you would need more large local populations different enough and populous enough for a larger state to try and eject them, like how Malaya unified with Sarawak and Sabah to avoid becoming ethnic Chinese dominated or majority, and then ejected Singapore. So I suppose you would need Bantustan sort of places, which would be difficult as India, China, Indonesia, etc all invaded any small area they could and claimed anything claimed by rulers in some of their territory centuries before. Having places with European majorities? Iffy. The Dutch East Indies company prevented Dutch people from settling down in the East Indies so they would not become competing traders, so we missed out on a chance to have them intermarry or get their own local population like with Boers and Anglo-Indians. I guess that is another thing, in how we classify Europeans. Do they need to be full blooded? Mixed race? Just culturally European? It is going to be difficult, because so often Africans or others voluntarily or were forcibly used to fill up small areas as laborers, otherwise I expect we would have seem Cape Verde and plenty of island and coastal places would be European. Really, it probably would not be appealing to most Europeans given the climate and how independent states would want to claim the city and whatever wealth they had for themselves. And if they were not wealthy or trading heavily with local states? No real reason to stick around in those climates. Better to head to Australia, Europe, or the Americas. Lots more land, lots more jobs.