Fair enough. but I think that our impression that the music from Haydn through Brahms (even beyond) seems constrained and non-diverse (and to a large degree I agree), has everything to do with the fact that we are viewing it from an entirely different historical perspective. Macro views hide micro changes. So even within the western classical tradition, the diversity as observed by contemporaries is not something so easily dismissed.
Nicely put ... but my comment was a response to: "If you want to play hobby music in the style of other artists some software tools make it easy to do so, but you never will find your individual style."