One thing I absolutely miss is being able to destroy improvements using Air Power. (and with the addition of ranged units - they should have this option too) The way I see it, given Civ V's repair an improvement mechanic. A logical option would be to create "More turns to repair" the more powerful the attack. There could also be a % chance at successfully damaging it, or a combination of the two. I.e. A longbowman would have a 20% chance of causing 1 turn repair damage to a resource. Whereas a Stealth Bomber would have a 95% chance of causing 5 turns. etc. Or the more complex model: Longbowman attacks Improvement, 70% Chance no damage 25% 1 turn repair damage 5% chance 2 turn repair damage Stealth Bomber attacks Improvement 10% chance no damage 30% 3 turns, 40% turns, 20% 5 turns. (Just as an example) Interception units could decrease effectiveness.