Food for Thought:
1. If you’ve already played the original PS3 version of the game, you can transfer your save to Ultimate on PS3 or PS4 via some save uploading shenanigans.
2. It doesn’t amount to much more than a fun detail, but I really liked how story missions would affect each other. In some missions a recruitable character will die, but if you complete a mission later in the game, you can, for example, take a catapult you found and go back to the earlier mission and save the guy from his untimely death. There are even smaller things like my troops in one mission getting a morale boost because they heard about one of my previous victories, too.
3. One of the quirks of the PS4 version is that your controller can talk to you. All of the character voices will come out of both the TV and your Dual Shock 4, which I imagine would be pretty neat if I understood what anyone was saying without reading the screen.