I have searched the current GW Guru site for any such suggestion but the closest one I've found is at the end of this post. So in case I've totally missed it, forgive me.
Purpose
The purpose of this suggestion is to improve the current chat box system.
Background:
The Guild Wars chat box uses a limited amount of colors for the chat system, colors which are very similar to each other (light green & green, mauve & crimson). The current method used to filter chat lines are by checking on/off boxes for the appropriate chat line.
Problem:
As it is, we only have 1 chat box for all chats and conversations. It makes it hard for people to monitor guild, alliance, team and trade chat all at once when they have to. Furthermore, when players call targets it's easy to miss a team member's chat line. The same goes when a guildmate uses the guild chat while you're in the middle of a farm run. Furthermore, this problem can cause people suffering from Dyslexia and the color blind serious misgivings.
Typical example:

I missed this person's entrance and he thought I was ignoring him, which was of course not the case.
Solution:
1. Insert an option allowing the user to add a second chat box.
2. Both chat boxes should have a new toggle option for the "system" chat (in GW's case it would apply mostly to drops).
The second chat box could by default be conveniently placed atop the current one and wouldn't allow the option of typing in it. It would contain the same chat toggles as the current one including the "system" addition. This way, the user could potentially set its boxes so that the bottom chat box would only display the Guild, Team, Whispers and Alliance chats, while the top box would display Trade, System, All chat, or any other desired combination.
Note:
An similar example has been proposed here, but I believe it lacked the possibility to properly customize the interface.
Also, someone suggested this but I don't think people understood what he/she meant.
I believe this would be a welcome addition to the current chat system and would satisfy the needs of the Guild Wars player.
Thank you.