Okay, so we already know the classes we have so far: Jedi, Trooper, and smuggler for republic, and bounty hunter and dark Jedi for Sith. I'll put down what I think the classes should be, and you can comment or put up your own.
1) Jedi - Force User
2) Republic Commando/Trooper - That's the sort of backbone of the Republic side
3) Smuggler - Quick, deadly, fast sniper sort trooper.
4) Republic Infiltration Unit - A balanced soldier who's fast, quick, smart like the smuggler and can hold the line in battle like the Trooper; I was thinking a mix between the two. Just thought this would be a good idea.
1) Sith - Force User
2) Mandalorian - I thought that this would be a good counterpart to the Trooper as the heavy assault soldier, since the Mandalorians fight for the Sith.
3) Bounty Hunter - Evil smuggler
4) Raider - Mix between Mandalorian soldier and bounty hunter.