The main airline in my country is Iberia there are another ones as hispanair, vueling or aireuropa. They haven’t good or original logos as Qantas that has a kangaroo.
Iberia decorates their planes with its logo that consists in a red I with a crown and a yellow B it represents the colours of the spanish flat and the crown of the King.
I don’t like this decoration I find it oldfashioned the alternative that I propose is paint all the plane in clear blue and include it different pictures of Spain and its main cities: the green forests of the north, the coast, the dessert of the south, Barcelona, Madrid, Sevilla, Santiago, Zaragoza…