Colour variation in the airline name

What makes a coaster unique and collectable. We start with looking at the 5 broad Types (including the sub-Types in two of them), and destinations within each Type. However, we soon begin to notice that even within the same Type, the same Destination, and the same Colours used, there are some variants. I will showcase some such variants here.

The collector can choose whether he wishes to collect such varieties as part of his collection.
Above: Two Type 1.2 Aden Coasters with the same Red + Green colour combination. However, the one on the Top Left has the airline name in Green, while the one on the Top Right has the airline name in Black.
Above: This time we have two Type 1.2 Tokyo Coasters with the same Blue + Red colour combination. The one on the top Left has the airline name in Red, and the one on the Top Right has it in Black.
We now have Four Type 1.2 Moscow Coasters with the airline name in different colours. Starting clock-side from the Top Right we have Light Blue, Purple, Turquoise and Black.