I am going to bump this thread, since Goldfool is looking for ideas for tundra terrain, and it is the sort of really different mod that appeals to me.
AndrewG, I will do a print out of your ideas and then makes some recommendations to you of things and people that you can add to the mod.
One additional American military leader you can add is this quite, unassuming individual by the name of H. Norman Schwarzkopf, who was the effective commander of the 172nd Infantry Brigade while I was there, with the Army commander in Alaska being Mark Boatner. Also, as an historical aside, the Simon Bolivar Buckner you have in the American military leaders list was the son of the Simon Bolivar Buckner that surrendered Fort Donelson to Ulysses S. Grant, and who was one of Grant's last visitors prior to Grant's death from cancer.
I should be able to help you some with Inupiat leaders, along with wonders. Also, you need to make Whales available in the coast tiles as well, since you have the beluga coming up into the Cook Inlet and the coastal areas along the Arctic Ocean.
I like your idea of the Temperate Rain Forest, as that is what the Panhandle actually is. I will see if I can come up with anything to replace Rubber, since that is the real odd resource out in the strategic resource list. You might want to keep Fruit in with all of the wild berries though.
I am a military historian, so if you want help with your Forgotten War scenario, I can help a bit there, and also one of my other areas of interest is Arctic and Antarctic exploration, so I should be able to help you there as well.