Here are my thoughts, for what they're worth.
I value Amex MR much more than UR (refresher-somewhat of a DL hostage where I live). That said, I don't value UR or my relationship with Chase as much as Amex. So...I don't shy away from Chase, worried they will shut me down. I am definitely LOL/24 and in November got both a R-C and Disney Premium (R-C for the travel perks obviously) and Disney Premium for the $200 credit. If they shut me down, then wow, okay, I don't have to pay any upcoming AF or downgrade/cancel my cards! If not, I'm going along my merry way.
I do think concern is warranted, even if statistically it's a 1/10000 change, if it's you it's 100%. So I absolutely don't play fast and loose with Barclaycard or Amex, don't worry at all about Chase or Citi. As with most things, I think it's how you value your relationship with that entity (Chase is a lot like my in laws, Citi like my brother's in laws whereas Amex is like my DD
and Barclaycard is like my dogs
).
As for AUs, my DD (17) is an AU on 2 Amex and 2 Chase cards. She uses the EDP primarily and the Chase IHG overseas and it has worked out well for us. If I decided to keep my CSP I might add her as an AU since I don't value IHG points very much. Thanks for that reminder
Interesting topics and I appreciate the discussion.