I thought x-force deadpool is member only? Normally, if you go to shop, you will see "Early Access" if the hero will be released to non-members. I don't think it is the case with deadpool.
For this theme, I like X-force Wolvie the best even though he is repaint, I can gloss over that fact because he has awesome HU. I like the brotherhood mission as well. Crisis brotherhood and Crisis A.I.M are best for vibranium farming I think.