I've always defended the prequels. The OT was an existential fight for survival under the oppression of a tyrannical government. The prequels were a grand political thriller that utilized tragedy to set the stage for the OT. Attempting to view them as within the same sub-genre has always been a mistake.
But tracing the plot from:
"trade guild doesn't want to pay taxes" -> "blockades a peaceful planet" -> "republic sends knight-diplomats to negotiate" -> "they discover a plot to invade, and an attempt is made on their lives" -> "they escape to the planet, warn some people (and rescue captive government" -> "escape, have an engine failure, wind up in the middle of nowhere where they coincidentally encounter the chosen one and free him from his bondage" -> "trade guild forms full-blown separatist union" -> "chosen one grows up in an apprenticeship as the order or knight-diplomats attempt to manage the situation" -> "both sides secretly build an army, and eventually a clash ignites a full-scale war" -> "war culminates in the destruction of the separatists, albeit at the expense of liberty throughout the republic, which is then declared an empire, as the knight-diplomats are treacherously betrayed and destroyed"
It couldn't have been any better, in my opinion.
Especially when you trace the thread of Palpatine as:
"senator of blockaded nation (secretly orchestrating the blockade)" -> "Ousts sitting chancellor and takes his place" -> "Secretly orchestrates separatist movement building an army" -> "Uses ensuing war to claim emergency powers" -> "Gradually consolidates power throughout the war until he becomes a de facto dictator" -> "Subtly manipulates the chosen one to gain his loyalty and plague him with fears about his loved-one" -> "Use his emotions to turn him to the dark side, reveals himself as a Sith lord, and orchestrates the betrayal and destruction of the Jedi Order" -> "Declares himself emperor" -> "Secretly builds a weapon of mass destruction" -> "Uses it to rule through fear and eventually dissolves the senate."
Scrutinizing the screenwriting and acting is fair, but I think it misses the point. Monet wasn't famous for his brush strokes. If you go to an art museum, and examine his paintings under a magnifying glass (you might get yelled at to stand behind the invisible line), you'll probably wonder why he's so famous. Back up a few paces, and look at the whole painting, and suddenly you'll get it.
For me, the prequels aren't about the acting. They're about the plot. And I find it expertly crafted.