Let's be honest here. It is debatable which colored hair is the best for girls, but there is absolutely no disputing that /a/, as a whole, prefers blue haired girls over any other color. Let's take a look at these 6 characters alone:

Erio - She is basically the cover girl for all generals on /a/. She was so popular that she was one of the picture representatives for 4chan.

Konata - She was basically /a/'s mascot from 2007-2008. Even today, she has a massive following in otaku culture.

Cirno - A major /a/ staple. From the GET threads to the general baka threads, you literally cannot go an hour on /a/ without seeing at least 1 Cirno picture posted somewhere.

Miku - Miku Monday.

Yin - Now I've lost it. I know I can kill.

Rei - Do I even need to explain this one?

In fact, blue haired girls are the upmost highest tier on /a/ to the point that people are already mad at me that I didn't include their favorite in the picture. That's just HOW MUCH blue haired girls are superior to the rest in /a/'s eyes.

Can you show me otherwise?