CSS only needs to be implemented as much as the site calls for. There is no standard as to what is needed, whether it be number of classes, nor number of lines of CSS needed.
A site that is all "in house" which CoasterBuzz is needs nothing more than simple CSS. Hell, truthfully if it wasn't for Club style switching there would be no need for CSS on here other than to speed it up.
CSS can speed up sites, eliminating redundancies in code. The more you have isn't necessarily better, it all depends on how much of it is used.
Shaun Rajewski
XtremeCoasters.com
Epic WebStudios Interactive, Inc.