TOTALLY agree... or even better, do what Epic is doing and finally use dedicated servers instead of P2P. But yeah, it's insanely frustrating to escape a firefight only to have bullets "follow you around the corner". Unfortunately, this still happens in BO now and then. Nature of the beast, as BD2003 said.
Well, the host advantage is really only a big deal on maps where everyone is running out crazy in front of each other like that. On a typical map, the host advantage is relatively small due to the client side hit detection.
Unfortunately it's not quite as simple a matter as just "delay the host" 40ms. There needs to be a golden standard as to what is actually going on in a game, and that standard is the host. It's really hard to explain, and without knowing exactly how their netcode is structured I can't quite put a finger on why it needs to be the way it is, but my intuition is telling me that it has to be the way it is unless they're using dedicated servers. But dedicated servers won't cure the jankyness, just the host advantage.
But I can say without reservation that it still has the best damn netcode of any multiplayer FPS out there. There will always be some jankyness as long as it's on the Internet, but they do a damn good job of hiding what lag their is, as long as you don't look too hard. If you do, you'll find it, but that's inescapable.