Firstly, talking about pure physical build here. Like Muscle vs Muscular build (All the frills removed) They are pretty comparable. In fact Uvo looks larger in musculature than adult gon. Obviously at the sacrifice of agility and muscular reflex but I was talking pure base build.
Link 1
^ Now that picture's scaling is WAY off. Uvo is 8'6" Confirmed officially. Adult gon is about 6'2-4" Fan based math, so he wouldn't be any taller than something Generous like 7 feet. Uvo would tower over Adult gon. But their heights aren't important. What i was trying to say is physical build is in the same ball park. I won't deny adult Gon's Body building career is looking great, but Uvo is definitely no slacker, he has more muscular mass than Adult Gon, hands down if you include the fact that taller body = more mass. Gon's muscle just seems to be much more functional.
Gon honestly eats Uvo's face in Aura, which has a multiplicative effect on an Enhancer's strength, which would cause a HUGE difference in final combat strength. But just basic no frills body build, it seems to go to Uvo, if you throw in the fact that his body is much larger in the first place and he needs easily like 40 extra lbs of muscle to cover it thanks to the height difference.
And I don't know how we would determine exactly how much Uvo 'trained'? I'm assuming he became an S-class mark in the Hunters association because of the fact that he trained his body to that point. We honestly don't know much about Uvo besides the fact that he lost in a fight vs someone whose abilities were created specifically for defeating him. Kurapika's speed should be a mute point i personally think, i mean he was always considered just as fast as Kill pre-hatsu. And we've seen that Killua could behead most enemies in the blink of an eye ff he calms himself into his assassin mind set and strikes. Also Kurapika was under death imposition. From what we've seen with Gon, covenants don't just affect your hatsu, but your base Nen/condition as well, it's invoked quite differently. Him being faster than Uvogin just seems like a natural reaction to his body being under that covenant.
Secondly, I only said that because when he was 'ranking' them in the anime (Not sure if this scene played out differently in the Manga, and if so I apologize) he seemed unimpressed by most of the ones present except for one. Who still wasn't quite as good as Illumi in his eyes. Which is valid when you consider how excitable he got over Gon, because he basically senses where gon's power is going to head in the future and wants an opponent like that. He's almost equally excited over Chrollo and the thought of the Upper tier spiders coming after him. And the thought of murdering Killua and getting Illumi to hate him.
So while they might not 'bore' him. He certainly is more interested/invested in 'playing' with the spiders and with Adult Gon.
-At this point Hisoka is going to become the unit by which all hunters worth are measured haha-