Well, I spent most of my time reading/watching Naruto just so I can see how the story would progress and mainly end. The progression towards the midway of the war arc and the ending were both terrible to me, and the ending was rushed like hell, all because Kishi wanted to end off on a pretty even number. He got lazy and knew what everyone wanted - Naruto vs. Sasuke, but he was running out of time "apparently" so he just gave us a bunch of crap with the Kaguya nonsense, and Sasuke's dumb resolve that wasn't going to happen anyway so why bother?
Kishimoto said in his interview that Jump decided the ending date 1 and half year ago. Whether Kishi deicided to end it at 700 instead of 699 701 would make very little difference. Only thing it confirms that they were talking about setting a date and plan for future. He said in that interview that he couldn't carry the story to the next chapters because of that and had a hard time trying to figure out to squeeze maximum in. So I don't think how it's fair to trample on someone work's work of almost 15+ years like that. That's a lazy thinking.
Kaguya up the scale of danger too to get the team 7 a real moment for themselves. Plus it gave a chance to Obito to redeem himself before his death - If it were a Naruto discussion I would say she was brought in to shift blame from Madara too. Kishi simply doesn't seem to like characters having no excuse for their actions. The ones who are simply ambitious or greedy they are killed off- Deidara, Hidan and kakuzu without much fuss. He tries to emphasis on understanding, consideration empathy and negotiation. Naruto's journey is about getting above his childhood dream of a hokage and be much more before settling for that.
Kaguya and Black Zetsu- no body knew them enough and didn't have sympathy with. Otherwise Itachi had to carry a mysterious illness to die from to give Sasuke a pass. Obito got Zetsu and Madara and Madara in turn got an alien to be saved from getting alienated and unforgivable himself. That's a whole another cycle. Plus to leave a thread for future extension. For what else is there to fight with but aliens after you already unite the whole shinobi world. Not a bad idea after working on something for this long. 15 years of serialization + the time given to the concept before.
Many people read One Piece for the different adventures and new people along the way, as well as partial development for the SH's. It's not just Luffy who is getting all the spotlight. He may be the one who eventually defeats the final villains of that arc, but there are other characters who have their battles as well. Oda likes to give everyone development, and he also knows how to give his characters depth when he needs to. Robin, Sanji, Franky Brook...etc..
That makes OP a different kind of story- more suitable for a long run with plenty of small stories. And these are the main SHs. If he wouldn't give any depth to them then who is going to tolerate them for 18 years?
In Dressrosa, we got to see many people doing their thing, like Franky and Senior Pink, the Tontotta soldiers, the members of the Doffy family, Cavendish, as well as huge development for Law and Doffy history. It wasn't just luffy doing everything or it wasn't just about Luffy.
Law and Doffy's story- first villain to get such an elaborate background story and my faovurite already - I say Oda picked from Naruto how to make them more memorable.

Just see the development Arlong got - after 500 something chapters!
If anyone else was there - I don't remember them. Not without a wiki.
If this was an arc in the story of Naruto, Naruto would be the only person doing anything, and I don't think many people like reading a story when only 1 person is receiving handouts and powerups while everyone else is left in the dust like a bunch of fodders, and that's exactly how the 4th ninja war was. Naruto and Sasuke were doing everything while everyone else was sitting in the background watching like a bunch of children. This is why you shouldn't make your characters too strong because it messes up the power level of the characters and then you have no choice but to make everyone else irrelevant.
Exactly what everyone else did at the finale in Dressrosa- pushed the cage and cheered for Luffy. Otherwise the commanders in war had their own fights. Even TenTen and Chouji had their own fights to win. There were many guys like the rubber guy or the samurai who had their moments.
That's why Madara was killed in such a stupid way. Kishi didn't even know how to beat him so he pulled this Kaguya crap and defeated him that way.
Madara's was actually killed in a very fitting and smart way. Kishi obviously knew what he was doing because unless he had worked out on the story he couldn't finish it within the given time frame. One wouldn't even know what to put in one chapter and what not without that.
In One Piece, It's not just 1 or 2 people getting asspull powerups and soloing everyone.
Yes there are. It's Luffy and Zoro. Otherwise it simply has tons of more characters so obviously they will do something. They have their small time villains to deal with.
Oda knows how to take care of his characters. Kishi only cares about Naruto and Sasuke, while leaving everyone else is in the background looking at the pretty fireworks.
The title of the manga should have been a hint on day one you know. It's not a a bowl of ramen every adventures ninja was seeking. But if Kishi didn't took care of his characters and gave them a likable personality then people wouldn't be so passionate about the two dimensional piece of art.
The only thing I'll give to you is that Naruto characters are easier to stick to and remember.
Not gonna get into this Naruto vs. One Piece thing anyway. But
I like One Piece while you don't..
And somehow you believe they are easier to stick to and remember because they are not written well.. how does that even work? Especially since Kishi's characters don't even provide much of the fan service?
I have been reading OP regularly since late 2011( had watched both anime at the same time and later dropped anime for both). But I don't fanboy it. It certainly isn't as well rounded as people like to believe.