Eloquent writing, by nature, makes an argument easy to read. In a creative context, eloquent writing leaps off the pages, appealing to all the mental senses to conjure a vivid picture that immerses the reader in what the author has to say. In a more scholarly context, say, a research paper, eloquent writing guides the reader by the hand through a series of potentially esoteric subjects. It allows the reader to focus on the argument the author is making rather than getting lost in complicated jargon. There is rarely a writing situation that cannot benefit from eloquent writing; eloquent writing elevates.
Flowery writing shares some attributes with eloquent writing. It too can conjure mental pictures, it too can appeal to the senses, it too can immerse the reader, albeit not as effectively. Flowery writing is pretty for the sake of being pretty, and it doesn’t necessarily elevate an argument; it can actually obscure the point the author is trying to get across. However, there is certainly a time and place for flowery writing, especially when a bit of obscurity is desired: poems and prophecies are some good examples.
Then there is the type of writing I refer to affectionally as “floofy.” In contrast to eloquent and flowery writing, floofy writing has almost no substance at all. Floofy writing dances around an argument without ever really touching it. It’s a tempting method to stretch out a paper in order to hit a page limit, but beware: floofy writing turns the reader in circles, round and round, searching desperately for order, for a guiding argument to follow, until he has read through three pages and is more confused than when he started. Usually, underneath all that floof is a single idea that could be described in just a few sentences.