Lately, I've been doing defense. I kept getting attacked so often at the beginning that I had almost nothing in my treasury. Now that I've raised my defense to above 14,000, I can pretty much repel any attacker for the time being. My gold is accumulating quite nicely.
I'm planning on working on my attack now, though, so I can start kicking ass and equipping every soldier with a weapon.
EDIT: To give you a little bit of an idea of how handy it is to have a good defense, I just repelled an 11,000 damage attack by the #284 player. :O