There will definitely be a Bounty Hunter class, I have no doubt of that. I may even go with it, probably. IMO, Bounty Hunters will be loners that fight for cash whenever bounties are put up on people. Should be a good way to play without actually hugging any alliance.
There will have to be some sort of Rogue/Thief/Scoundrel class that will be skilled in all sorts of tricks and abilities. They will probably end up most valuable when adventuring with battle-geared players (of which I think there will be too many
Some sort of a Scout class, that may strike a balance with Scoundrel and Soldier. I'd rather it concentrates on speed, reconnaissance, scouting etc. It would be interesting if you can play as a scout and chart out an area with stealth and then sell the map to the highest bidder, with info such as treasures, enemies etc.