Is it possible, for a optional user-controlled feature, to create a window within the actual channel's text scroll area, similar in the way that ChatZilla does it.

I am referring to the part at the very top of the below window, which shows Channel Topic / Modes etc, Example of the window in ChatZilla:
[img]http://puu.sh/1UREh[/img]

This information is already present in the channel/mIRC titlebar (depending on if your channel window is tiled or maximized).

I don't see the major difference your request would make.