At first I loved it, but... I've changed my mind. Honestly, it just seems like another restriction. Civ V is all about restrictions, not about exploring possibilities.
I dislike SoD's as well. Neither do I enjoy ICS. There are many ways to prevent this, but Firaxis chose the easy part and just added restrictions. Building that extra city causes the entire nation to stop working properly. A scout is enough to hold off an entire invasion of another Civ. I don't like restrictions like this, because, what they basically are saying is "We don't want you to play like that, so we are just going to stop you from doing it."
But my belief is that Civ should be about possibilities, not restrictions. Make a well developed city far superior to a small one. Let small cities that are not connected to the capital face a huge corruption that may lead to riots and revolutions. But also add governments/civics, buildings, techs etc. Put these techs on a different branch than the military techs. Suddenly, the player has the ability to expand quickly, but on the other hand he will not have military power to protect his cities. Let the militaristic player solve this issues by controlling the riots with military units. Make it hard as hell... but make it possible, and make it possible in many different ways.
Same thing with 1upt. Let the attacker chose which unit in the stack he will face. Add some collateral damage. Problem solved. Suddenly, stacking a bunch of knights and crossbowmen wouldn't be such a good idea... The player would be able to stack his units while not at war, when passing a choke point or an enemy scout, but it would mean suicide to put the units in a SoD when entering the enemy territory.
In other words, these "restrictions" are just a way of solving these gameplay issues in most plain way there is. A project like Civ should mean years of planning. But the feeling I get is that Shafer got some basic ideas about 1upt, hexes and global happiness and then they said "let's say where this takes us", without doing any brainstorming at all.