Reduce business class

Veggie first airline should be implemented. Not only for Sustainability reason, also to meet the modern traveler expectations

Bio fuel / green fuel as default, and having to pay more as a passenger if you want to fly on fossil based airplane fuel.

Separate the salt and pepper from the rest of the table set. Way too often it's just thrown away.

In Plus and Business on long haul - hand out amenity kits by request instead of placing them on all seats.

Incentivize sustainable behavior, e.g. a small reward for bringing your own coffee cup. This can also be sold by SAS in the Eurobonus store or in flight.