I'm not digging the opacity of the popups much (set at 94%, but still). The text underneath clashes to much with the contents of the popups.
I know this is a personal preference, will there be a way to customize your experience in the chat room?
No, this won't be possible. If you'd like to tweak the styles that much, we recommend Greasemonkey or some other method of force-overriding the CSS.