I don't think Credits should be used for anything, when they are awarded for all things that are essentially Out of Character. So gaining a reward, such as spending your credits on a rare material, item or ship is an In Character reward for Out of Character things. Everyone who knows me as a writer knows that I don't like OOC influencing IC. This is my stance on it.
I also find it a little redundant. Credits are used as a reward for the number of likes you get on a post, blog entries etc. But isn't the like system there to show that you as a writer, as well as the content you've produced on the forum, has been well liked or received by others? That someone enjoyed something you've said and the quantity of likes on your profile shows that you as a writer are well liked as well? I don't see the point for credits.
But eh, go crazy guys.