I love this freaking map
It's absolutely amazing. However, I have two predictions. There are two large areas with no countries inhabiting them. East of Shurima, and south-east of the Freljord, between Demica and Noxus. I have a feeling that the one west of Shurima will become Nidalee's home, the Kumungu Jungle. It makes sense. In her (really short mind you) bio, Nidalee's parents where treasure hunting and what better place to do that then the crumbled empire of Shurima. Assuming that Nidalee ever gets new lore, its where I would place it.
The second unmarked land area, I think will be the site of the Demican/Noxus war. Ionia has repelled Noxus. What better thing to do then now march west and start taking that unclaimed land. That will undoubtedly cause strife in Demica and the Frelijord. Demica will prepare for all out war, while the Winter Claw (
tribe) will use the growing fear of invading Noxians as a reason to draw more people to their side