Ideas for achievements

Handled planes of an specific airline (for example: Handle 100 KLM planes of all tiers S,M,L,X)
the reward could be golden planes or W it deppends of the difficulty of the achievement
Handled planes of an specific model ( I know that this one is in the game but it could be extended and put more with game money for reward)
That ideas could improve the benefits with small rewards and make the game more fun