What decisions would they make? How would they solve the problems they're faced with? What decisions would they make? What endings would we see for the DLCs? What endings would we see for the base game? And quests with no ending slide that, nevertheless, have drastic effects on people's lives?
I think it's an interesting question that puts each nation into perspective. For example, I see House working with the Kings and the Followers to improve Freeside and Westside at the cost of the NCR (help Tom Anderson, turn the Kings against the NCR, help the Followers fix addiction and get the pump working) as well as preventing the launch of any nukes in Lonesome Road (Ulysses' survival would depend on if House saw him as a valuable, intelligent "worker" or a psychopath), but I don't see him giving a damn about Joana, I don't see him showing any mercy to the White Legs, he would intimidate Dean Domino and he's really only helping the Kings and the Followers for as long as it helps Vegas.
Then Caesar. Would he assist the NCR at times to gain their trust? Would he nuke the NCR? If you ignore his personal stake in many things, Caesar actually seems like the type to evacuate Zion, and the type to understand Ulysses. He probably would set Helios to give everyone power (after killing all the NCR there), he would bother to help Joana and he would get along with the Followers.
Finally Kimball. This guy's really simple, so you just follow the NCR's plans at all times. He'd end up opposing the Followers, he'd kill Hanlon and definitely kill Ulysses and nuke the Legion. The Khans and BoS would both be dead, but the Kings would benefit greatly.
I'm just curious to hear what people's thoughts on the matter is, and how they visualize each leader acting.