And a suggestion about creating an army:

Create an even amount of buildings and army simultaneously. Buildings require tons of crop, which is expensive, so that will hold you up. But troop creation requires very little crop, leaving you with tons of excess which isn't even valuable in the Marketplace. Build even amounts of both at once to balance this out.

I avoided creating troops until necessary because I didn't want them draining my crop and I didn't want them sitting idle in case they were attacked and killed (all the resources they cost could be lost in a few attacks). I still feel this is a solid plan, spending all week creating only troops now that I want to attack.

I was saved from the overabundance of crop by the Grain Mill; once you have a Cropland 5, you can build it to get 5% bonus on Crop. But, it costs a TON of crop. No problem, because crop will build up while you create troops. A Grain Mill is a cost effective way to burn up this excess crop and allow you to support more troops!

So, either create even amount of buildings and troops simultaneously, or prepare to micromanage trades for crop during building-only creation and micromanage crop surplus during troop-only creation.