The era is actually fine, this gives BW a huge open spot to put in their own lore and all that. Whereas if they did it in a different era, they would have to be careful in how they would go about making the game and trying not to disrupt any lore....especially if the game was set during the movies era, then your really limiting what is able to happen.
I was thinking about that too. A lot of people would get mad if you messed up the EU lore. However, I think the majority of Star Wars fans don't even know what the EU lore is, and couldn't care less if you messed it up anyway.
I think LOTRO did a really good job of this. This game could have gone on concurrently with the original trilogy, that would have been great. They frequently have areas that are set either right before or right after events in Lord of the Rings. Star Wars could have done the same. For example,
Hoth - when Luke left, the last of the Republic forces were still clearing out. Empire forces could be trying to round up the last of these Republic forces, especially trying to capture critical data or people before they got off planet. Republic forces could be trying to save them from the Empire's assault.
Alderaan - right before it's blown up. It would be cool to see everything, knowing you're going to be one of the last people to see the planet before it explodes. Both sides could be tracking down rumors of a secret Empire superweapon headed their way...
Endor - right before the battle. Republic players could be out recruiting Ewoks (kind of like the Twi'lek pilgrims on Tython).
Tattooine - pretty much any time!