While reading Blackest Night Flash 2, I thought about many things surrounding the characters :

(1) Rainbow Raider :

He could alter people's emotions by coating them in certain colors.

Since his death, he has been replaced by a gang of colored criminals, using the 7 colors of the rainbow, like there are 7 colors on the "emotional spectrum".

In a funny kind of way, you could say that Rainbow Raider was a main source of inspiration for the current storylines in the Green Lantern books !

(2) Cobalt Blue :
Barry Allen is a Blue Lantern !

It is very interesting, since his supposed evil twin, Malcom Thawne is the villain named Cobalt Blue !!!

Not only that, but the power of the villain is based on a "blue flame which could steal anything his heart desired".

It is very close to the powers of the Lanterns.

(3) Magenta :

OK, she does not appear in Blackest Night but would not it be logical if, somehow, she was linked to the Star Sapphires (given her past behaviour) ?