[Maranna]

You can speak to the Aldor and the Scryer quatermasters before you chose your side. This was you can see what they have to offer. Talking to them at this point won't affect anything. As matter of fact my hearth is set for the Aldor inn, though now that I have chosen the Scryer, I should probably change that...

Lower City is just like any other city rep, as is the Sha'tar. Or is as far as I can tell.

As far as talking to a banker I think that just set your starting point with them. If you talk to the Scryer one it will also set it. Then once you chose sides, it will go from there