I guess that the OP is not being lucky or is on a serene age, he must have a good farmer layout with upgraded arty towers and mortars, wich scares the hell of most pillagers, specially Medievallers.
I understand the OP's confort on GP Age, because the most outlandish things that will be thrown at him are gatlings and guerrillas (oh mah boi, I want some defensive gatlings units to laugh my azz off at medal goers on my turf). On EA he can be attacked by planes and zeppelins and all that modern stuff wich is more than a regular mild upgraded base at EA can normally deal.
Well, I made peace with the fact that some otherworldy EA army can crash the party at my GP base and mop the floor of my little Nobunaga, but well, the attacking/defending concept is more balanced than CoC, where depending only on medal level, a guy with EVERY units upgraded to max can chew the bones of a player with a LVL 4 town hall. I'm moving foward on this game, because if not, I will never put my hands on the the shiny guns of next age and at some point I will become a self-service for raiding armies. I'm staying on Gunpowder until there is no building and unit left to upgrade on my city.