We haven't seen Mon Mothma or Ackbar yet.
Or Leia.
Leia might not be involved.
If I were Bail, I would be keeping her as far from the rebellion as possible. I would bet that when she does get involved, it will be against her father's wishes - or perhaps after Bail is killed. (We don't know how he dies or when he dies or if he dies, only that he's never seen on screen in the originals, but is around during the prequels. But it's a common reason why people get involved in politics in the real world: They had a relative who was assassinated for their views, so they take up their mantle.) Or maybe she doesn't get involved until immediately prior to A New Hope , Bail giving her the Death Star plans and telling her that there's no one else he can trust to go to Tatooine and recruit Jedi Master General Obi-Wan Kenobi.
http://www.starwars.com/databank/bail-organa
According to SW.com he was on the planet was it was roasted