Good point on the other stuff. I should add that also have my Global Entry renewal soon, and I know amex has a credit towards that, not sure about Delta Reserve though.
I am also Hilton Diamond, but I use work corp card for that too. As far as i can tell there is no way to link my corp card (Amex) to a private card in any way - or pay the difference and upgrade corp card to reward card.
Uber or other ride discounts don't matter as I only use them when I travel, and I am not paying for it.