I have been wanting a huge map for a long time and performance is not an issue really, I like to build BIG so I'm used to performance hits.

I have Shigo Islands mod but really, it's not all that, only slightly bigger than the standard map and you need rafts/fliers to get around because none of the islands are linked at all. I like spending time to get around to gather resources, marching an Ankly miles to gather metal etc. With a large map, considering the number of dinos now in the game, you have more chance of finding things like sheep and other animals that usually get preyed upon to extinction as soon as they spawn. At least you can set up a spawn point for them away from most of the predators. The standard island map is too crowded for that.

My main problem with a large map in single player is the time it takes to load the game. Shigo islands takes close to 15 minutes to load a saved game in single player and that's with a SSD.