I’m in the same scenario as OP and for me, I’ll really miss CPUs (my luck is better than most as I’m often on full Y tickets and take advantage of the “instant upgrades”), availability of the “expanded” business class award availability, no waiting to talk to a United phone agent, and fully refundable/changeable award tickets.
I’ll make gold this year, but I’m tempted to mileage run on AC so I can get platinum specifically for the award availability to drain my account before more devaluations.