Now, my brother, sourfreak99, just got banned for not changing to trade change. The reason is because he doesn't
focus on chat (While trading though I don't know how he doesn't). I don't blame him, I sometimes decide to zone
out from chat as well. Before this turns into a ban appeal and not a suggestion, I would like to say that you should add a plugin making it so that a moderator can post a message to a specific player and their WHOLE screen will be filled with a notification message such as but not limited to: Change to trade chat, stop spamming, stop annoying other players, stop using caps, and stop being inappropriate. Then of course there should be an automatic phrase should be added to the bottom. I believe that this phrase should be the old but all purposeful, "or else you will be banned!" This would help the server by helping out all those members that ignore the chat and don't see a moderator's warning in chat. Then it would help them from getting banned for avoidable things like using caps.
Pros:
Less players get banned.
Less annoying problems in chat.
Avoidable problems can be avoided.
Cons:
Requires a plugin.
More typing for the moderators.