My population was reduced by 75%, which I think was benefited by having hospitals in as many locations with over 120k population (the Yucatan is very dense) as possible. Which was like, seven. I could have maybe done more but you really need your cabinet developing the high pop provinces because they also need 20 development for a hospital
even then, hospitals in 90% of my high density locations only seemed to change it from 80-90% population loss to 75%. My first run I had like 5.3 million population, ended at 1.03 million, and in this run I had 1 million fewer to begin with and ended at 1.03ish as well
Perfidious Castile declared war, got spanked, refused to land even after The Great Deadening, so I white peaced and have focused on consolidating the Aztecs. The largest Aztec player, Tepanecapan, is my junior in a personal union. Pretty much everything that existed prior to colonization from the Yucatan to central mesoamerica is owned by a vassal (except for a tributary who I can't make into a vassal because they made that really hard for some reason)
so even severely weakened the high unity might be why Castile hasn't tried to fuck with me again despite having 110k levies to my Whole Situation's potential 29k
anyway GOT SOME TIN CAN'T WAIT TO BUILD A REAL BOAT!!
Funny thing is that in my Aztec game, Castile didn't even bother to show up. Aside from England and Portugal colonizing North and South America at a comfortable distance from Mexico, there was the Two Sicilies, the Papal States and god damn Bulgaria, and none of them really took an aggressive stance against me. Made the second half of the game's timeline a cakewalk, albeit with me still grasping how the economy works.
Yeah, as it stands, NW nations are very rough around the edges and obviously have been playtested last.