I thought I'd finally turn on ironman mode to get some achievements. Having noticed that very few people have the "own Timbuktu as Songhai" achievement, I thought I'd give it a shot. It turned into this:
(My holdings marked with a glow to easily show my colonies as well)
The game got very frustrating during the last 100 years, as Portugal and Britain constantly declared wars to reconquer their cores. Eventually I always defeated their uncoordinated landings and won, but could not, for some reason, demand that they revoke their cores.
My personal biggest achievement during this game was this:
Resulting in this after 6 years of war:
In total, I got 17 achievements during this one game.