My apologies if you've discussed this elsewhere (I haven't been able to be as active here lately), but do you have any plans for the PRG? I believe travel direct through Amex is the only cat maximized by PRG in your current lineup, and I can't imagine SBS and the occasional Amex Offer would be enough to justify keeping it indefinitely.
Edited to add: the ability to slap down a gold card has value to some, but you don't strike me as the type
I'm not sure what the situation is with booking airfare through Amex travel. I haven't done it, but I do get 3x points on airfare booked directly with the airline. Travelocity-type websites would not qualify for a PRG bonus (though they would qualify for CSP as "travel").
I'm keeping PRG for now, under the following logic:
1. I will almost certainly be flying for Thanksgiving and/or Christmas. If I wait to designate an airline for the $100 fee credit, I can buy my ticket, then pick that airline, and use the $100 credit in full for checked bags and food - especially if I travel with a companion. The air credit, and the fact that I can wait to pick the airline for the first year, is a big factor.
2. My PRG anniversary was in late May, so I think I qualify for the $175 AF, even though it won't post until later this month (the end of the 13th month).
3. Some of the offers are nice besides Small Business Saturday. $20 off $20+ at Samsclub.com, $5 off $5+ on iTunes and Google Play. I just checked and PRG had an offer for $50 off $200 or more at Brooks Bros online. EDP and BCE didn't have that one, and an offer like that can beat most BB card exclusive offers.
4. I do like it that it's shiny and has a high charging limit, but it also doesn't require travel notification. Several months ago, I flew a thousand miles to visit relatives. I forgot to put travel notifications on my cards. We went out to eat at a restaurant, and other people wanted to pay their share in cash. I put the cash in my wallet and put the whole thing on PRG. I was only getting the base 1x MR, but the transaction went through smoothly. I've had false alarm fraud alerts on Discover and CSP, and wouldn't want the hassle of needing to use a different card. People in my family often talk about money and know how others are doing, so it's not like people would think I had bad credit. It's still an inconvenience, though, and would be a reputation problem around people with whom I wasn't so close.
5. I'm also considering a PC to Platinum. By keeping PRG alive, I can save myself from an inquiry and a new account. At least, as long as I can break even with PRG, I figure I'll keep it.
6. I did get regular AAA, so roadside assistance is no longer a PRG consideration for me.
*7. I also have the sneaking suspicion that Amex will nerf ShopRunner as a perk, and reserve it for only some cards.
Maybe I will close it someday, but for now it makes sense to keep it. It's definitely not an everyday purchase card, though.