6. Professor Xavier (Marvel Comics)
I have previously touted Xavier as the ideal candidate to wield the indigo ring of compassion, given that he will take any young mutant in to his institute after the rest of society has rejected them. However, this also makes him suitable for the blue ring of hope. Professor Charles Xavier, leader of the X-Men and founder of the Xavier Institute which is housed in his mansion in New York, is a hugely powerful mutant telepath with the ability to control, manipulate and read the minds of others. Even the most misguided and troublesome young mutants are welcome in his institute, which shows them that the world isn't entirely against them and offers them hope in the face of adversity. Coupled with his genius level intellect and leadership qualities, a Blue Lantern ring would make Xavier an even more formidable individual and would make him a physical threat to his enemies as well as a mental threat.