I think this is a problem mostly in the entirely settled islands like EC. There, if your city is at half production and your potential targets have their regions at full production, then it makes a lot of sense to wait, because your capabilities will increase while your targets capabilities are already maxed out.
On the other hand, in places like Beluaterra currently or Dwilight, it makes little sense two wait. Sure, maybe in six months you will be twice as strong as you are now, but so will your enemy!
I think the solution is simple: more war, and more destruction. When everyone has a large proportion of devastated regions, then everyone is equal, and there is no reason to avoid war, thus perpetuating the destruction cycle.
