You need to read Literature (big L right?) and not just literature (little l) - Pulitzer is not necessarily quality in terms of the style of writing, often it's based more on the content.
I would say you need to read more of the "classics" by which I mean those books popularly referred to as classics but which aren't in the true sense. Plus modern writers of literary fiction, essayists, poets and speeches
My own personal favourites:
Austen
Dickens
Bronte sisters
James Joyce (notoriously tricky but try the Dubliners to start with)
Orwell (but I would say not animal farm as that's quite deliberately simplistic in its language)
Arthur Conan Doyle is superlative at expressing himself in few but well chosen words
Dh Lawrence
Jonathan swift - gullivers travels is a delight but also take a look at his essays (I especially like a modest proposal - odd that it was written by someone who would become a Tory really) and his poetry
Poetry I'd steer away from more prescriptive forms and look more at free verse forms Walt Whitman And maya Angelou are my own favourites
F Scott fitgzgerald (start with gatsby as it's a fairly easy read but then move on to other works)
But also the genuine classics - which are less easy to digest true, but seriously learn the building blocks of speaking eloquently, debating persuasively and commanding attention for the right reasons. Look at Cicero, Pericles, Demosthenes...
Listen to and watch great speeches made by great orators, and debators, I actually think more the debators as they're having to think on their feet and respond carefully, notice not only what they DO say but what they DON'T - how they control themselves, use body language etc speeches are good but they're honed and prepared sometimes for months so it's not a natural way of speaking necessarily but good for building vocabulary.
For speedy, witty responses check out Oscar Wilde, Shakespearean comedies, PG Wodehouse and similar
Do you sing? It's very good for training the physical aspects of speaking, breathing and controlling the diaphragm, vocal chords and breathing - and timing!
To be truly articulate does take practice (record and critique yourself, ask trusted others to watch/listen and critique) learning the correct techniques (tons of articles online plus videos and tutorials but choose wisely) and building confidence (nobody starts off confident - fake it till you make it).