Maybe use a Fermant Spiral pattern? Here's a few with varied divergence angles.
Edit:
Be aware that our hitbox and shotgun spread are the original ones. They're exactly what it's always been in GunZ on the official servers. (So you're really complaining about the original shotgun spread and hitboxes)
I told you [the community] about the random shotgun spray and it was brought up a long time ago by players, some of you have been there and seen it, we've done multiple attempts to fix it and gave players different options and let you play with different spreads for weeks (or months) even. All in all most of you said they want the original spread back, Ganggbangg is right that I told you it would not fix the issue of inconsistent damage and probably only make it worse, but most of you still wanted the SGV (vanilla) spread - and you got it. (I didn't wanna say I told you so, but yeah I told you so)
Shotguns with 12 pellets are certainly never gonna be perfect, that's just not possible with shotguns w/ large spray and this low amount of pellets (you see the same inconsistency in other popular games).
But at least it currently is the original, untouched, vanilla GunZ way.
Now that I think about it. Not fixing anything might be the way to go. RNG creates a lot of clusters which is actually the clustering illusion, so players may be experiencing something similar to the Texas sharpshooter fallacy, where people focus on where they didn't hit. In other words, people will complain no matter what.