I've gotta say that overall, the arc I didn't like was the War arc. Apart from Ace's death, it just didn't do anything for me. I'd rate it 6/10, the lowest I'd give an OP arc.
–- Update From New Post Merge ---
Okay, now I understand your beef with the Tiger portion of the flashback better. You're right, Oda could have done way more with the raid on Mariejois. Maybe he's planning to return to that at some point in the future? Seems doubtful now they're past the Red Line altogether though. But then, there are a lot of FI plot threads that still need resolving (like the prediction that Luffy would destroy the island).
Well, gangs of doofuses is pretty much the shounen mainstay, innit? No one's saying One Piece is masterful literature.
Really Gliblord? You posted this?
Not seeing what's wrong here. Japanese children's pulp comic villains are hardly that realistic, in the end they're still cartoon villains. I mean, you could say the same about Wiper's gang, couldn't you? They were also beset by a legacy of war, but they weren't very fleshed out either. Not to the level where they were gag doofuses, but there was Eneru's gang for that.