As i have struggled unlocking the "Cosmographical Meditations" achievement, i've beaten the game second time, thinking that it glitched for me the first time, and then realised that it was not the case, because i've uncovered all the "pink fields" on the map twice and didn't get the achievement. So i basically just randomly ran into one unexplored area and decided to create this to save time for others. Hope that it helps.

P.S. You dont need all vistas, mycelium and compost maps for the achievement, just uncover all the "fog of war"