The answer to your question would be that the sentence that correctly uses hyphens is the following one: The quick-thinking, well-dressed speaker shocked the audience.
Because "well" is an adverb, some might say that it should not be punctuated. Yet as compound adjectives can include adverbs, the compounds with adverbs are usually hyphenated when they precede the noun they modify.
As regards, "quick-thinking", these two words also function as a unit, they stand for a compound adjective. The speaker is quick when thinking.
