Rachel Grey - Excalibur

Rachel Grey (http://en.wikipedia.org/wiki/Rachel_Summers) is the future daughter of Cyclops and Jean Grey... Or maybe of Cyclops and the Phoenix Force posing as Jean Grey... Or maybe it was Cyclops and a Jean Grey who was just possessed by the Phoenix Force... She sometimes has the power of the Phoenix, and came back in time after one of the shittier childhoods in comics to join the X-Men and then Excalibur.

Getting The Look
The facial tattoos that Rachel Grey has as a hound and Phoenix are so distinctive that it's bizarre that there is a mask in DCUO that replicates them perfectly. Yet that's exactly what the League Of Assassins style face let's you do.

Psylocke - Australian Armor

Psylocke (http://en.wikipedia.org/wiki/Psylocke) and the X-Men lived in the Australian outback for a while, and despite the desert heat she thought a suit of armor was a good costume choice. It was bright pink and lavender, because of course.

Getting The Look
This costume is more of and endgame look, with only two pieces being available at character creation and one that is only obtainable at CR99. You'll also need to be a Legendary member or have both the Origin Crisis and Amazon Fury Part 1 DLCs.