Let me define Island Paleo first:
You are stranded on a desert island. The island is small, and variety in foods is limited. Amazingly, this island seems to fit all the stereotypes one would see in a "Lost" sort of island. Namingly, you have access to fish, coconuts, fruit, and spring water.
I had a thought to recommend this type of diet to two sorts of people: recent vegans/vegetarians, and those who do well with limited foods when trying to lose weight.
On the positive side, it is sooooooo simple. Steam some fish, add some form of coconut, have fruit for desert. Maybe some veggie or herbs to add flavor or use as wrapping. Hundreds of fictional characters have survived this diet and had their amazing stories told. Tom Hanks, John Locke, Joe Kitava, etc etc. The cast of Survivor always has some dude who loses a ton of weight with this diet (duh, there's not much food around and not too many things to choose from).
Here are potential cons I can see. First, there is not much variety. The importance of variety is debatable. Lowering toxin load is a real thing, but might not be a big deal with these foods. One can easily get a variety of phytochemicals by eating different fruits. The second thing is that eating a ton of fruit might not be great if you are metabolically broken. Some paleohackers might not think it's great even if you're healthy. Third...is there too much omega 3 and not omega 6 in this diet? What a crazy problem to have. I'm assuming here that spearing the local boar is too unpredictable and dangerous and will lead to a Lord of the Flies type incident, and that tubers are hard to find for the time being. Leading to problem number four: is it hard to get enough calories eating the Island Paleo diet? Tubers usually would be a great source of calories, as would fatty red meat and associated marrow and stuff. I guess you could make fish jerky to keep around?
So anyway...thoughts on Island Paleo?