[@Sep] see the way I picture it reed doesn't have the right head for it.  He gets too distracted by science and has a deep wounded conscience because of what happened.  Susan on the other hand is the get up and get shit done kind of person, and more than once has acted basically as leader.  I don't think anyone would object to her stepping forward.

Also yeah stretchy powers aren't normally leadership, but I see more the symbolism of it rather than just he/she is stretchy so by default they're leader.