Going back well before launch after the classes were confirmed one of the big ideas was how they would add more classes down the line,
Firstly they had to met the standard Bioware wanted for them, EG an Iconic Character we could relate to them and still be able to be mirrored by the other side, so what we basically had idea wise was two things, making faction swapped versions of two existing classes, plus to more accurate mirrors
So, Bounty Hunter would get a Republic version, and Imperials would get a Smuggler.
This was also debated whether or not to allow a faction swap in their class stories so you could change faction.
The other idea the community had was adding two classes
The Imperial Commando, based around the Iconic Stormtroopers, the Empires elite but this time with much better aim! You would be a Tier 1 operator for the Empire, leading an Elite squad taking out high level Republic Targets
The Republic Officer , based Around Leia, Political dealings, back stabbing and undercover work story wise,
These two also act as better mirror classes than the current mirrors, as Commando/Trooper and Agent/Officer align much better than Trooper/Bounty Hunter etc
But this was a time long ago, before the panic and drastic changes all set in