What should a liberal arts education provide?

So my broad understanding is that there are two important components to education.  On the one hand, education is vocational: that is you learn skills relevant to a profession.  On the other hand, education is liberal: that is you learn skills relevant to life as a free person.  It seems to me that we've lost sight of the second goal, that the current liberal education is a historical artifact that has lost its most useful characteristics and kept its outdated ones, and that our educational institutions owe it to us to have a rethink along the lines I describe.

Wikipedia has some historical background on this that seems relevant to my rant.  For those of you who hate clicking links or fear Wikipedia, the liberal education (the education for free people, as opposed to for slaves), was basically verbal reasoning enshrined in the Trivium of Grammar, Logic, and Rhetoric, and (eventually, once we got to the middle ages) mathematical reasoning enshrined in the Quadrivium of Geometry, Mathematics, Music, and Astronomy.  It's worth mentioning that the Quadrivium is probably better understood as Statics, Number Theory, Ratios, and Mechanics, but they used useful proxies for the names instead.  Whatever.  It seems that between the Trivium and the Quadrivium we have basically all the tools necessary to explore the depth and breadth of human achievement.  That makes sense, since that's basically the point of having a liberal arts education - to give you the tools to understand and contribute to discourse in the free world.

Now, it seems to me that while the tools described in the Quadrivium enjoy broad support and advocacy in education, they are the least useful, and indeed increasingly antiquated, tools.  The Trivium, by contrast, seems to be all the more vital today as in the past, and is given considerably less attention.  We basically fail to explore these ideas in depth or with formal rigor at any point in the liberal education - saving perhaps brief flirtations in philosophy, theology, or literature.

The modern world is increasingly (to its great credit) a quantitative one, but those quantities are large and their relationships complex and stochastic, wherein the past what numbers we encountered were limited in scope and mechanically related.  To engage with these new kinds of numeric data, one needs a strong understanding of probability and statistics.  To reason at all, one needs Logic.  To speak precisely (a precondition for any useful debate) one needs Grammar.  To speak well, one needs Rhetoric.  Perhaps, along with Statistics, we should consider something like Aesthetics: a discipline dedicated to effectively and convincing displaying things (in this case quantitative data).

It seems very much to be the case that learning how to recognize and generate well reasoned arguments--precise in language, and effective in style--and to support or analyze such arguments with ready knowledge of the proper treatment and presentation of statistical/numerical data is a key skill to avoid being deceived and to defend one's beliefs in the modern world.  How is it that our institutions of liberal education have so uniformly failed to acknowledge these needs and address them?