If Alex Mercer gets in, we need DLC costumes for them that portray their rivalry started by Yahtzee of Zero Punctuation.
I think colonel volgan from snake eater would be a perfect fit for the roster. They could have the shagohod hanger as a stage, and have his moves centered around using bullets and electricity. He is a character that is often forgotten in the metal gear universe, but he had a major role in shaping the future big boss. Lets get him in the game superbot!!!!
demons souls (knight, penetrator), i second all final fantasy (cloud, sephiroth, tifa, squall, barett...)/soul reaver/caine, lara croft, tony hawk, tenchu assasins,
please add ashley/sydney from vagrant story