So, as to Jeheira and Misnc being non-origin 'companions', I don't see why everyone is assuming they will be true companions that take up a party slot instead of a camp follower and / or party extender (like the myconid or Halsin when you free him). It'd be pretty odd to down scale their power to a level 5 character (about when you'll find them I assume). I fully assume they'll park themselves in your camp doing 'something important' and maybe we'll be able to have them join us occasionally (final battle of act 1?).
