Great post by StellarW.

I typically run on VH/H or H/H (depending on faction I'm running) using quite a few of those houserules.

I would add one to it also: No siege fights. If they attack you and you take the city fine, otherwise leave the siege in place. This will slow down your expansion, allow the AI to rebuild (over 4-10 seasons) and tie up in early game a significant amount of your resources effectively making it very difficult to exploit via blitzkrieg.