http://bugs.kde.org : File a wish (immediately visible to the developers)
Yeah its a wish so it could go there however
http://www.kde-apps.org - When it's about new functionality
It could go here because althought it isn't really new functionality just moving some current functionality into a different place which then
http://www.kde-look.org - When it's about a new look
gives it a new look meaning it could go here
It might be posted in the KDE4 Brainstorm forum
not sure about here though
Theres no code involved although code will have to be changed, I've just done a image of an idea
send a message to kopete-devel explaining the idea and be sure to include any screenshots or mockups as links to the images. Please be willing to accept rebuttals, more suggestions, etc. to your idea.