Well, I'd call the show 'uneven'. The orchestra is upstage, housed in a 3-tier structure, visible during the Hot Box numbers, but hidden behind a screen during the rest of the show. Projected on the screen are distracting and annoying CGI graphics (left over from WOMAN IN WHITE?) that do nothing but take away from the actors on stage.
Another gimmick by director Des McAnuff is to have actors arriving out of the orchestra pit like sea creatures in a bad 1950's Japanese 3-D horror movie.
You are correct about Craig Bierko and Kate Jennings Grant having the best chemistry, since Oliver Platt and Lauren Graham have none. As Nathan Detroit, Platt seems to be alternately channeling James Cagney and Fred Flintstone. As Miss Adelaide, Graham avoids any of Vivian Blain's iconic characterization, but fails to come up with a memorable one of her own. You never understand what attracts them to each other.
Yes, "Sit Down You're Rockin' the Boat" just about blows the roof off the Nederlander (despite the idiotic clouds being projected on the screen), but neither of the Hot Box numbers really get off the ground. The Crapshooters Ballet is nothing short of thrilling, and the big, creamy Loesser ballad "I've Never Been in Love Before" simply soars. Perhaps as the cast gets more comfortable in their roles, they'll relax and simply enjoy the fact that they're in one of the best musicals ever written. If that happens, I think we'll relax and enjoy it more too.
'Our whole family shouts. It comes from us livin' so close to the railroad tracks'