This wouldn't really have been a problem except some of the actual quests took that even further. The description of Elara Dorne's accent as "pure Dromund Kaas" looks bizarre to anybody with even a passing familiarity with Star Wars lore - it's by and large the same accent that Bastila Shan, Obi-Wan Kenobi, and Ki-Adi-Mundi share.
Please don't forget that this thing is mainly lost in all other language versions of SWTOR - and the movies, if they are dubbed, too (like here in Germany).
The Agent, Warrior, and Inquisitor all change their voices when attempting to pass as "not Imperial" in various contexts (e.g. the Foundry flashpoint, or the Agent's undercover mission on Nal Hutta). Clearly we're meant to think that that accent really is restricted to the Sith and the Imps.
A point which no-one has yet brought out before is the possible similarity to
- Greek at the time of the Romans
- French during the time of Napolean
- English nowadays
as being the "upper class language".
During Roman times, and many centuries later in the lade Medieval times / early Renaissance times, there were Greek and French languages known as THE languages of the world ! Who wanted to belong to the upper classes has to speak those - and it was a sign of being well-educated, as well.
The accent thing might be a similar thing - although it is only an accent.
Another thing not mentioned yet is the assumption of
British Accent in Stasr Wars -> Military in Star Wars.
In the *original* ideas of Star Wars, the Empire was conceived as an fashist / fascist state. It went so far that the original "Star Wars" logo contained German letters in the end, meant to be an expression of that.
I wouldn't be surprised - after what I've learned during the last decades - if George Lucas had imagined all Imperials to speak with an German accent instead.
But - he chose two top notch actors : Sir Alec Guiness and Peter Cushing - which were really excellent actors ! (The autobiography by Sir Alec Guiness is a good resource on stage acting in the first half of the last century !)
And - they were British, thus speaking British accents. And George Lucas didn't want to change that (or he would have done it, like with Darth Vader - have you ever heard David Prowse acting as Darth Vader BEFORE his voice was dubbed ?).