People are forever concocting classes that replace the standard ones: the present author produced an ukart class that used the sober package, and a few British-specific things (such as appear in the babel package's British-english specialisation) in the 1980s, which is still occasionally used.
Similar public efforts were available well back in the days of LaTeX 2.09: a notable example, whose pleasing designs seem not to have changed much over all that time, is the ntgclass bundle. Each of the standard classes is replaced by a selection of classes, named in Dutch, sometimes with a single numeric digit attached. So we have classes artikel2, rapport1, boek3 and brief. These classes are moderately well documented in English.
The koma-script bundle (classes named scr...) are a strong current contender. They are under active current development, are comprehensive in their coverage, produce good-looking output and are well documented in both English and German.
The other class currently under development is memoir. This aims to replace book and report classes directly, and (like koma-script) is comprehensive in its coverage of small issues. Memoir's documentation is very highly spoken of, and is sometimes recommended as an introductory tutorial on typesetting.