I worked some more on collecting keys and smashing gargoyles in Fable 2 tonight, and I think I’ve got most of them except for the ones in areas I haven’t reached or areas blocked-off until later.
There wasn’t much else to do, so I finally headed off to find the third hero, a pirate in the town of Bloodstone, and I had to go through the new area of Wraithmarsh to get there. I encountered Banshees there for the first time, but they weren’t too tough; their only gimmick is that you have to kill their summoned pets before you can damage the banshee herself. I reached the town, and the hero turned out to be an arrogant ass who wants me to do a suspiciously easy favour for him before he’ll help me.
Some other sidequests back in the previous regions also opened up once I reached there, including areas I’ll be able to find more keys and gargoyles in, but those will wait until after I finish dealing with this guy.