I think such a new card will be like a combination of Plat/Brilliant/Aspire with a touch of Green, with the credits structured to increase breakage.
$1650 AF (3x Plat, 1/3 Centurion... Makes geometric sense)
Same Uber credit as Platinum
6x on travel (amextravel and direct with airlines)
3x on transit/taxis/rideshare
2x on Hilton/Marriott direct
Bonus 1x on Delta
$100 quarterly airline fee credit
$50 quarterly Saks credit
$100 CLEAR credit
FHR benefit
Lounge access with guests (lower cards lose guest access)
$75 quarterly Starriott credit
Bonvoy Gold (Titanium after $25k)
$100 Ritz/St. Regis credit
Hilton Diamond
$125/6 months Hilton resort credit
$100 Waldorf/Conrad credit
Ability to redeem 10k MR for 1k Delta MQDs
Maybe "Platinum Preferred"?
Doubtful that Brilliant or Aspire holders would move to this (the hotel benefits are a bit watered down). Might complement the DL Reserve (MQMs from Reserve, MQDs by MR). Definitely beats Plat+Reserve+Aspire+Brilliant, but you'd still want a restaurant card.