That top picture has all the matchups wrong except for Yusuke and Elder Toguro.
And, much like my feeling for Rurouni Kenshin and the Makoto Shishio arc, I think that Yu Yu Hakusho could have ended perfectly well at the end of the Dark Tournament. It had sufficient build up, gave plenty of time for you to hate Toguro, all the characters had breakthroughs and got stronger, and it ended perfectly climatically.
Now, I haven't seen the rest of Yu Yu Hakusho past that very far, like I did for Kenshin (watched all of that, and I'm
certain it should have ended with Shishio). So it's hard to say whether or not the end of the series was in fact more fitting or climactic, because, as I said, I haven't seen it. But I could see the series ending after the Dark Tournament, with Toguro in your mind as the baddest mofo around (Surpassed only, of course, by Yusuke), and it would be pretty good like that.
But my final verdict is: undecided. That's a pretty crappy verdict, actually...
EDIT: Also, it's just typical of the genre. Take DBZ:
"Hey, you know how Raditz was so tough? Well this guy's even TOUGHER! How will you ever win?!"
"Hey, you know how Vegeta was so tough? Well this guy's even TOUGHER! How will you ever win?!"
"Hey, you know how Frieza was so tough? Well this guy's even TOUGHER! How will you ever win?!"
"Hey, you know how the Androids were so tough? Well this guy's even TOUGHER! How will you ever win?!"
"Hey, you know how Cell was so tough? Well this guy's even TOUGHER! How will you ever win?!"
"Hey, you know how Fat Buu was so tough? Well this guy's even TOUGHER! How will you ever win?!"
"Hey, you know how Kid Buu was so tough? Well this guy's even TOUGHER! How will you ever win?!"
"Hey, you know how That-Metal-Baby-Dude was so tough? Well this guy's even TOUGHER! How will you ever win?!"
"Hey, you know how Dragon-whatshisface was so tough? Well this guy's even TOUGHER! How will you ever win?!"
...I never got farther than that last dragon guy in GT. But you see my point.