Honestly, I think that would be a good idea...or at least some sort of "exclude forum(s)" function in the advanced search. Right now, you can choose to search any one forum, but you can't run the same search simultaneously across several of your choosing.
I used to run TeaChat through an external search engine (usually google...I'm lazy) to combat the difficulty of searching the archives, but the larger TeaDay gets, the less helpful even that becomes.
BTW, neither Chip and I are Adagio reps, nor can we do much in the way of site construction. Ilya's the guy you want to hear back from. You might want to PM him, actually.