I don't think the question is 'who would win in such a fight'. The Zodiac will most definitely win or nothing even makes sense about the power hierarchy of this world (The Hunters are the guys who are supposed to be hunting down people like the Spiders).
Note that even if you want to lead a life of crime, Pariston shows that with sufficien tpower and deception you can be part of the Zodiac and continue doing nasty things. Okay you can't probably can't do straight up mass murder (they'd get you kicked out fast) but there's definitely a lot of potential room for corruption even in the Zodiac.
The only thing I can think of against being a member of Zodiac is if dressing up as an animal is a necessary criteria.
Hunters hunt anything from treasure, food, plants, animals, killers, Jewelry.
Pariston is tolerated because of the challenge he put up agasin't Netero in his career. Netero likes a challenge, and very much like Gon doesn't solely judge on Good/Evil.
They dress like their respective animals out of respect of Netero assigning them a sign and have adapted it to their personalities. Except for Gin and Pariston
Hisoka ranked a few and wasn't that interested in a few ranking Illumi higher than the one's he rated, he's even looking for Ging!!!!! And not all are combat specialist but posses cool or great nen abilities....Doesn't mean it can't be bypassed or out muscled with similar skill.
I Vote Spiders. I rather be a bandit kill and steal whatever I wanted and be supported by others who are motivated the same way and have my back during these missions. Zodiacs aren't a cooperative group they know of each other and seem to have crossed paths through Netero or trough the HXH association but they each do their own thing. Spider's are a stricter group and have a code amongst Thieves, they move in pairs and those pairs are the close to each other
want to speak with him so much 
