You should be able to pre-select seats as *G
You will have business class /*G check-in at SFO and AMS/CPH
*G Bagage allowance (= 1 extra bag)
Lounge in SFO is in reality only UAs RCC - with the timing of the SK flight
Priority boarding
Decent in seat comfort, with small but OK selection on music and film
Pillow and a basic blanket
Meals can be a bit of hit/miss. Have not done long hauls Go in a while though
Once in CPH you will arrive at the C gates, clear immigration (but not customs) - and once through continue straight to the SAS lounges - upstairs is the Gold loung with better drink and food selection (but usually more crowded). Immigration can take anything from 2-15min.
You AMS flight most likely will depart from the B gates. Easy 10-15 min walk from the lounges. May also be at the A gates - add another 5min.
The CPH-AMS leg is rather basic, water, tee/coffee is free - other items are charged.