@Nex:
Here's the thing. This battle is unwinnable for Oda. There are people like you who are upset that the NFP were not interesting, underdeveloped, and didn't really do much, and then there are people who are upset that Hyouzou was interesting, developed and then one-shotted by Zoro.
Now here's where things get interesting: it seems as if these people are one in the same. If everyone here knew that the SHs would not struggle here, then you should be happy that Oda did not put a substantial amount of time into dveloping all the NFPs. If he had, then this arc would be even longer with the same result of the SHs easily besting their opponents. See how this is a problem.
The only way to solve it, is for Oda to make the enemies interesting, but also have the crew struggle with them. That was never going to happen. Not with Oda at the helm.
I'm aware that Oda is in a bit of a difficult situation on how to approach this arc, especially coming off the timeskip. The fact that some people will be displeased regardless of what he does is inevitable, but you can say the same exact thing about any arc in this manga. Just look at users who say which arcs they like or dislike. They are some who are pleased and displeased with the other arcs; however, it is not a question of winning every single fan with the story, but trying to decide a path that will please the majority.
And, given the nature of this arc(its story and themes), it seems incredibly important to develop the NFP, regardless of whether the Strawhats are going to easily defeat them or not. Part of this story is about racism and slavery. Why not go more deeply into the characters who are affected by these problems? You make it sound like if Oda had given the NFP more development, that automatically means it is required for the Strawhats to struggle against them. I disagree. Also, if people were more invested in the fate of these villains/characters, that means there are potentially more people who would enjoy the story. If that was the case, then more people wouldn't mind it being a longer arc. My enjoyment is not entirely dependent upon the battles. By improving the characters, Oda could have at least improved one facet of this arc.
My problem is that some people treat the story of FI that we have now as if it was the only logical way to approach it, like it was inevitability in every way, shape, or form. I disagree.
Edit: Oh, and about Hyouzou. He was interesting because he had a good character design, and was hyped up by the author through the mouth of Luffy as "strong." And he was not developed. He was a character with potential to be developed but that didn't happen. And honestly, I remembering thinking, since he's probably a mercenary, he may not get the same development as the others, but at least, we should get a somewhat decent fight with him, even if it means Zoro getting the usual handicap. Of course, that didn't happen. sigh.
If anyone thought otherwise, then they obviously do not understnd how Oda writes his story.
Also, anyone who is dissapointed in this arc has themselves to blame for over hyping it. I do believe Oda always intended Fishman Island to be where the SHs show off their strength.
Although blame can be placed upon fans for having great expectations, the expectation for Fishman Island to be something great has stemmed from what the author has given us throughout the story. The foreshadowed heavy issues of racism and slavery has started from an early part of the story. Not to mention that what happens on Fishman Island could possibly have serious repercussion on various aspects on the future of the story and character(s). It's like people are suggesting that we should have all thought, "Oh yeah, just another normal arc. Nothing to expect here."
Also, as for the Arlong thing, I am willing to wager that Arlong could beat Hodi, somewhat easily.
Well, presumably, Hody is the strongest of the NFP. So, in other words(though two of them have transformed), the Strawhats are showing off their great progress by beating up antagonists that are weaker than Arlong. That's just wonderful.(sarcasm)