I'd welcome a cleaner looking design any time -- as long as it doesn't sacrifice any usabilty.
Despite it's old-fashioned look, the perlmonks interface is very usable, once you know your way around. I don't want that to change.
People sometimes think the perlmonks UI suck, and want to improve it. Those people often aren't here long enough to have learned which parts matter, and many of their proposals would lead to a nicer looking design with decreased functionality. (That's not always the case, I just want to make you aware of that trap).
Others are longer here, and recognize the value of the current UI. Those often implement small, incremental improvements, for which I'm very grateful.