Getting more passengers on a bigger modern planes on certain routes will lower the emitted carbon dioxide per passenger as well as optimize the use of flight crews.

Option to make a plant a tree donation. By having a partnership with a existing tree planting project.

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

Dynamic seating - people with checked in baggage should be placed towards the rear of the plane as they are more likely to have to wait anyway on arrival at destination.

Same amount of points earned from origin to destination regardless of amount of flights.

Enable paid upgrades to Bio tickets online after agency/company booking is made, so employees can override restrictive company policies and gain more level points