Hyatt isn't really a back-up program in the sense that there are very, very few places with a Hyatt and no SPG option (and if you're a domestic US business traveller there may well be none at all).

So that leaves Hilton, Marriott, Priority Club, or stepping down a level and doing something like Carlson (whose domestic options outside of major cities are really sketchy) or Choice.

None of the big three have particularly great redemption schemes after recent changes. So I go with Hilton because I do enough stays a year to keep Gold which has pretty good on-property benefits. Also, I tend to find many HGI properties and even Hamptons to be better than the Marriott or PC alternative.