Things I really liked about this arc (in no particular order):
-Robin's past; probably the most touching scene was the "dereshishishi" conversation Robin had with Sauro, and its revelance later on in her flashback. I cried so hard after Ohara was destroyed and she was laughing as the boat floated away from the island.
-Clover's revelation; there's so much we found out about the WG and the past of the world of One Piece in this arc. I can't even remember how many different theories members of this forum began to spit out after Clover revealed his theory.
-Sanji following Robin; he completely and wholeheartedly believed in Robin when others doubted her. His desire to prove her innocence touched me.
-Franky; initially, he seemed like another silly character, but his conversations with Robin touched me a great deal. Outwardly, Franky seems very loud and obnoxious, but he's the sort of individual that really understands other people. My love for Franky only grew as the arc continued.
-Spandam. I'm a huge Robin fan, but I found his dramatics incredibly amusing; he's incompetent to such a huge degree that you can't help but laugh.
-Robin beating up Spandam. After all she took from the man, it was nice to see her finally lay it down on him.
-Robin's "Igiteru" and the burning of the WG flag and the departure of the Going Merry. Here was the real turning part for the arc; things will never, ever be the same for the Straw Hats.
-Aokiji. I love this man so much.
There wasn't anything in particular I HATED, just things I would have liked to see go a different way:
-After seeing Sanji so willing to do anything for Robin–even follow her onto a train full of powerful government officials--it was disappointing to see him faulter in front of Calipha simply because she was a woman. The dedication we saw in the earlier chapters of the arc seemed to vanish right here, and I was left feeling disappointed.
-The fights. If there's one thing that will turn me off to a manga, it's prolonged fight scenes. This arc had so much fighting that for a couple of months, I didn't read at all. Also, for once, I'd like to see everyone work together against a massive villian; generally (the exception being in the fight against Aokiji--and even then, Luffy eventually ended up being the only one fighting), the Straw Hats each fight their own opponent with Luffy fighting the strongest. I'd like to see the Straw Hats have to work together to defeat a major opponent, each using their own skills and expertise to contribute to the win. It's a little tiresome to watch Luffy always fight the major battles by himself.
Questions I'm Looking Forward to Seeing Answered:
-What was Aokiji's part in the Enies Lobby incident? Clearly, he influenced Robin's decision to leave the Straw Hats, but why did he do it? Why did he let Robin get away not once, but two times? Did he want the Straw Hats to defeat the WG? What relationship does he have with Smoker?