We all know there is a problem with nukes in the game. Specifically with shields. There is no balance with shields being permanent and only 250 geos.
If you have a city that is worth defending against a nuke, which means you have enough troops for it to be worth someone using a nuke against you, IE over 100000 troops, 250 geos is a pathetic joke compared to what it costs to make it worth nuking something. Kills balance, and strategy.
I propose that nuke shields should cost 100% of the income for a given city for a day, and last for exactly one day. It should not be cheap to defend against nuke attack. It should be bloody expensive and strategic. (I'd have to assume that this fictional shield technology ain't exactly cheap. This ain't Star Trek Wars)
What would then help the balance a bit more is the previously proposed ideas about Nukes having lasting effects on cities.
You should really have to sit down and think twice before either nuking, or defending against a nuke.
Lastly, if 1 day nuke shields are introduced, I think that this information should NOT be publicly displayed. When you go to nuke somewhere, you shouldn't know that it's shielded until your attack fails.
Add it all up, and I believe Nukes could actually become a viable part of the strategy of this game!
Talk amongst yourselves :)