You kind of hit the nail on the head by saying that "every line reading" of Patti's was spot on. That's what her performances tend to be: a collection of line readings. And they get more arbitrarily eccentric with each passing year.
Maybe- maaaaaaybe- playwrights like Noël Coward and Oscar Wilder can live by smart and clever line readings, but George Furth ain't Wilde or Coward and his linseed to sound as real and natural as possible.
I'd vote Josh Gad. He has a slightly obnoxious side that I think is good for Pseudolys. James Corden would be good, but he's just so likeable. (I think Corden would be ideal for Bill Snibson in ME AND MY GIRL.)
I found SWEAT a noble play, sincere in its attempt to document a section of America we don't get to see onstage very often, but a bit of a letdown in its execution. The dialogue often veered into sloganeering and some of the performances didn't help: you could see the actors' self-consciousness in their speechifying.
It seems that these days TV is tackling this kind of story so much better. Personally, I hope we have more of this type of subject matter in all ou