I think program-wise, Hyatt has the best right now after Marriott Bonvoyed SPG.
But in terms of footprint, Hyatt has far fewer locations than Marriott or Hilton, which can really inconvenience DH if he has to travel and can’t find a suitable Hyatt nearby.
Comparing the two biggest chains, Marriott or Hilton, I’d probably go with Hilton’s program if I was paid/reimbursed for travel. Remember,
@disneymagicgirl’s DH travels a lot for work and tends to stay at Hiltons. Maybe she could chime in? I guess the major thing is with Hilton and paid stays, it’s so easy to earn lots of points. Unfortunately, I think your DH needs to charge travel to the corporate card, right? So he wouldn’t get the additional earning power of charging a Hilton stay to the Hilton Biz, Ascend, or Aspire. But these cards could still boost him to automatic Gold or Diamond status, which would give him a bump in the points he earns for stays as an elite member regardless of what card it gets charged to, and would give him the perks of room upgrades and free breakfast.