My opinion on kurapika's nen vow and nen vows in general

To be honest I believe that nen vows cant grant you more power than you can have ( your full potential ) basically it's some sort of shortcut that you can use to access your full potential or atleast some part of it more faster but in exchange you have to pay the price

In my opinion if kurapika hadn't done the binding vow, he would've eventually be just as strong as adult gon or even stronger due to his special ablities and stuff.

He could've prob become the top 1 hadn't he taken the vow to only hurt spiders, but I mean thats just my opinion. But its understandable, he only wanted to avenge the spiders and nothing more, he didnt expect he would have to hurt anyone else other than the spiders with his nen.