Offer a ”Sustainable Comfort Kit” with eco-friendly amenities like reusable water bottles, organic snacks and bamboo sleep accessories

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

Stop giving away perks for children. They'll all end up in the garbage anyway.

Add green flights on some departures. nothing is served on these flights, only hand luggage is allowed, but you earn more Eurobonus points if you choose such a departure.

Engage travellers actively through the app: compete to save energy related to travel (pack light, public transport, direct flights) & display flight energy-consumption

More level points to trips that are more sustainable and have less legs and layovers to promote more direct travel.