There is no reason for us to think gon is anywhere near as good a fighter as gon... Overall killua is the one that has been the better fighter of the two through all of the manga which makes sense considering the sheer amount of training killua has gone through. Heck, even when gon and killua faced some ants early on we actually saw how the ants were able to discern killua was the superior fighter (they noted killua's movements were flawless or something of the sort). Killua is as far as the manga has shown superior to gon in terms of nen and fighting technique. Heck, killua actually showed he had the greater volume of aura during their second training with bisk. We even saw killua barely holding his ken when gon was basically already down.
As for transformed gon... I don't think there is a human alive that could match that. First of all we have to consider that pitou was actually able to defeat kite easily. Kite was without a doubt a high level nen user and even then he did not stand a chance. Heck, we know for a fact that in terms of sheer volume of aura the royal guards were actually superior to netero. Netero had more skill in terms of aura hence how he held his ground against the king but overall he was still inferior, perhaps massively inferior, to the ants in terms of amount of aura. And even then we have to consider netero could very well be beyond human as a fighter.
Remember when we saw how netero started his training? He was a 46 year old man who had apparently spent his life fighting. He did not go there hoping to become strong, he went there to give thanks to martial arts. He went there feeling he had reached a limit to his martial arts. I would argue the manga at that point was making the point that netero by then was already a extremely proficient nen user at least. Basically at the time he would have been in the same league at least as the current zodiac or the adult zoldycks. So basically what we have with netero is that he was already a high level nen user who them went through the enlightenment the manga described to become massively stronger than faster. Honestly, after seeing what netero could do, I can't imagine a human being actually matching him. Remember when mereum fought netero and just wondered how he could have gotten to that point? At the moment mereum speculated that reaching the point netero did was something that could be done by abandoning oneself to some sort of madness for 5 or 10 years... Overall I don't think netero would be someone who could be matched by just about your run of the mill proficient high level nen user, it would have to be someone who actually had it in him to find some insanity like netero did and abandoning himself to it for at least the same amount of time netero did.
Which takes us back to transformed gon.... That transformation was not just anything, it was the realization of gon's full potential. Killua made the point that such a nen should require years or decades worth of training. What kind of training? Who knows but its not too far fetched that that being gon's full potential was the nen he would have acquired after a lifetime worth of being subjected to some sort of insanity like netero did. It sounds like a lot but I would argue the notion is not too far fetched. Transformed gon didn't just have nen comparable to the royal guards, he had nen comparable to that of the king. The king was presumably not just stronger than the royal guards but rather MUCH stronger. So gon with his transformation would have presumably had nen as strong as the king's at that point. Now, whether he would reach netero's skill, which is what made his fearsome, is a different matter and we have no real way to know it. Still, we have every reason to believe the sheer amount of nen gon had was well more than the royals and at least a match for the king (pitou noted that gon could reach the king).
So as far as ging and silva.... To begin with I don't think either of them would have a chance against netero. Heck, seeing the crater left by the bodhitsava thingy it would not even be far fetched that it was roughly comparable to uvo's big bang impact which left a similarly sized crater in the ground. Of course the amount of nen in the attack does not even have to match the big bang impact considering the sheer speed at which netero can attack. Taking in consideration hisoka's judgement of the zodiacs it does seem illumi himself is actually stronger or comparable to quite a few of them. Nen does relate to a great degree with age as nen does take decades to develop so it kinda makes sense that silva would be stronger than illumi. And of course we have the fact that silva has quite an insane physical build.... It makes a lot of sense that he would be physically superior to ging considering it. As far as nen goes, who knows.... Netero did have quite a high opinion of zeno even though zeno is quite old himself, if zilva surpassed zeno then it wouldn't be weird at all that he was a comparable nen user to ging. And even then, nen is a very relative thing when it comes to fighting. There are many factors which could influence the outcome of the fight. Anyways, with what we know we can't really assert that ging was stronger than zeno even if netero thought ging was among the top 5 nen users. For all we know zilva's abilities are perfectly suited to fight ging for example.
....
I guess you've never heard of neferpitou then.
did you even read the manga? or you are thinking about a nuclear bomb in this world? because they are no the same...
