What do you mean by Oda's handling of Ace? His death? I think this event played an important role in Luffy's character development. It even still played a major role on the crew's development we've seen in the Fishman island arc. I agree though that WB should've died a better way.
For the story to come to where it has, Ace had to die and the Marine Ford arc had to happen. It serves the purposes of (in order of priority):
a) Forcing Luffy to realize his weakness, and inability to stand on the "big stage" of the world's pirates as he was.
b) Killing off white beard in order to start the beginning of a new era
c) Setting the stage for black beard
d) developing a bunch of characters, both former WB pirates and marines (and of course, Jinbe, Ivankof/Revolutionary arm)
All these are key points to the arc, but the arc itself was set up very badly-- especially with regards to killing off ace.
Ace is Roger's son, Luffy's adopted brother, and until marine ford, was the representative to us, the audience, of WB's crew and the virtues of pirates in the new world. The point is, he's a very important character to the universe of One Piece-- but we barely knew anything about him!
Bottom line is: we never saw any character development between Luffy and Ace at all, which fucked up the marine ford arc a lot. :|
If someone asked you about the bond between Luffy and Zoro-- you could go on and on about it. About Luffy saving Zoro from corrupt Marines, about the dual with Mihawk, their mutual trust in each other's strength and compatibility. If you asked about Luffy and Nami, you'd hear about the tear wrenching tale of how Luffy saved her from the terror of Arlong, and what it meant to Nami. Luffy and Usopp, Luffy and Chopper, Luffy and Frankly, Robin, fuck, even Luffy and Hachi.
Luffy and Ace? What did we know at the point of the shabondy arc (before impel down)?
Uh... they're brothers. Therefore they love each other.
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...
...
:|
When you rely on the bonds between characters for the plot, you need to show (NOT TELL) the development of said bond. Oda is normally really good at this, but with Ace he basically just fell flat on his face. The whole Marine Ford arc is based on the importance of Ace and Luffy's bond, which wasn't established AT ALL.
"They're brothers, therefore Ace is important to Luffy." Too bad that One Piece has completely ignored the importance of familial love up until now-- at least with Luffy's family. Up until Marine Ford, we see Ace and Luffy meet once and exchange a brief conversation. We see Luffy and Garp reunite after who knows when and barely care at all about their reunion (Luffy's more annoyed than anything). Fuck, Luffy didn't even know he had a Dad, and really didn't care about it. Familial loyalty had never been a big part of Luffy's character until Marine Ford.
SO when Luffy suddenly went ballistic about saving Ace (especially when up until this point, Luffy had been against "interfering with Ace's adventure"), it was REALLY out of character. Not only was it weird for Luffy to do, but from the perspective of the audience, there was no reason at all for Luffy to go ballistic, aside from "they're brothers."
Sure, I think Oda realizes he fucked that up AFTER it was all said and done, and then tried to back track and ass-pull a flash back sequence to FORCE IN a relationship between Ace and Luffy after-the-fact, it didn't really mean shit because it was too late...
This "brotherly love" relationship flashback was as bad, forced and pointless as a ship written by a crazed yaoi fan girl.
Throwing it in after doesn't work... for the entirety of the Marine Ford arc I was sitting back thinking "what the fuck is going on," because I didn't understand at all the importance of the relationship between Luffy and Ace.
God, don't even get me started on how awful and pointless the flash back arc was too. Usually when you use a flashback, you're trying to develop something that develops the story going forward-- but that flashback sequence totally flopped on that point too. Ace was already dead, so establishing the relationship after-the-fact was both meaningless to the plot going forward, and cheap ass-pullish since it didn't really alleviate the annoyance with Marine Ford. On TOP of that, Sabo got killed off (his death is not just "assumed" it's actually "confirmed," Sabo is in fact dead). If Sabo had possibly lived, than maybe the whole flash back sequence would have had SOME point in developing an important future character, but Sabo is in fact dead (more annoying is that this was confirmed not in the manga, which leaves room for interpretation, but in an official One Piece data book, which is just dumb).
Essentially, Ace should have been developed more, USED MORE, before he was killed off. Ace was a character so pivotal to the story, and with so much potential in terms of power, heritage, connections-- man, it was such a waste story wise!
This could have been done so easily, at so many points in the story. Ace could have played a bigger role in Alabastia; he could have been thrown in during one of the adventure arcs...
Fuck, it could be as simple as... when Luffy noticed the Vivra card shrinking, he could have shown a bit more concern-- he could have stared at it by himself at night, and one of the other characters could have approached him and asked him if he was worried about Ace, and about his relationship with Ace-- then Luffy could have gone into flash back mode, and we could have gotten the whole Ace + Luffy + Sabo child adventure BEFORE Marine Ford, which would have been fantastic because than the whole arc would have been way WAY better. Instead we got, "hmm, it worries me, but Ace is strong so it's cool. Let's ignore it and keep going without developing this point more."
Oda really flopped with how he used Ace, but it's really the only big issue I have with the One Piece story so far.
Also, White Beard, in his final battle not killing/maiming ANYONE important... -_____-