Will Swenson on his name alone would not really light up the box office, but I do think a savvy PR team could get some prime coverage of this and get the married duo out there in the press so that it becomes a big story that husband and wife are performing together. That could certainly generate some interest. However, I don't expect Audra and Will to want this. When they were in Beautiful Noise and Ohio State Murders at the same time, both of them remarked how difficult it was navigating their home life (their kids) while doing 8 shows a week at the same time.
The investor papers estimate the weekly running cost at about $1 million a week. So producers are determined to get stars. But I think, as others have said, they will have much more luck getting a big box office draw to take on Louise. And they will probably have to go with a big theater name for Herbie. I'd sort of love to see Brian d'Arcy James take it on. He's played more challenging roles for sure, but he would pair nicely with Audra and if this turns into a hit (which I believe it will) it could be what finally lands him a long overdue Tony win.