I don't see any plugin that would actually improve JB. It is just people who improve it. You know i wanna say something. Back when i was first in the forums, i played JB. I found that most people just wanted to build a reputation for their admin apps, that's it. They wanted friends for supports etc... Now most of them are admins and cba to play on JB since they don't need to after building their image. Unless we get more players who actually play JB because it is fun instead of rank, then you will see an improvement. People who don't just follow last reaction and first reaction, creative minds who want to have fun together and play it like a game, that is what we need. JB has good plugins although the piss plugin sounds nice

but the rules can be loosened up to avoid frustration of freekills etc..
Also tip for admins, try not to ignore players who are freekilled or have an issue, i know it is hard when your name is spammed for help, but you applied for that very reason, to help. You must put yourselves in the players' shoes and think, "Well, that players sounds annoyed and needs help and i am sure if i was him i would not like being ignored and continue to frustrate". Always treat players equally, make everyone feel they are apart of the great community and enjoy the game together, only then they will enjoy JB since they know, they are not just ghosts on the server but actual people who know they are also part of the fun.