I'm looking for someone able to create a plugin that locks people to a limited number of players they can interact with, and has a sliding scale of punishments for players who spend too much time in proximity with other players.  There are a few options out there that do something similar, but they're all either easily circumvented, or can be abused by teams to harm other players.  I've got a few ideas for specific features, but lack the know-how to create this.  We're more than happy to throw some money at the problem, if someone's got the programming chops to make it happen.

Hey, would love to see a few suggestion threads for Group Limit ;)

Interesting idea, but almost impossible, since as soon as players learn about the existence of such a system they will try to mimic like they are not playing together, transfer loot via killing each other, using separate bases, etc. Simple restrictions to a player base is possible however it is easy to abuse. 
An extreme solution is to write a deep learning model, train it on the real server with admin/mods as teachers and then use that trained model :)

I assume you want more than a group limit?  Eg, if they spend lots of time together, ect

That's sort of exactly what I'm after, yes.  The previous, now-unsupported plugin that I was looking for served to tick up an internal count with each tick that people spent within X range of one another, and once that value reached different thresholds, it imposed higher and higher debuffs/penalties.  Something like that is pretty much exactly what I'm after.

Sounds like an interesting plugin, I could do some experimenting and let you know how the result turns out.  Any specific type of penalty?

I was more or less looking toward Plagued for functionality.

I too am looking for something silimar to plagued functionality