This is an alternate time-line Saga edition game where Anakin Skywalker was never discovered on Tatooine. Of course this has far-reaching implications on the timeline, but it plays out similar enough. It is set in 2 ABY, with the players part of a team in the Alliance, who are regrouping after the severe loss at Yavin IV.
First note, Palpatine still becomes Emperor. However, due to not having Vader, and lacking a suitable replacement for Dooku (Obi-Wan kills him in this timeline) he does not manage to Eliminate the Jedi as efficiently as he did in Canon. While he does have an apprentice (A young Human going by Darth Tendus) and they destroy the Temple, a large number of Jedi manage to catch wind of his plan, too late to stop him, but soon enough to save a lot of the Jedi Archives and get the word out. with this, the Jedi Temple still exists, just on a smaller scale. The Empire still declares Jedi a dangerous enemy though, so be careful going out in public.
Of course, no Anakin means no Luke and Leia, meaning that Episode IV plays out differently. Long story short: Death Star wins, even with Jedi assistance. Rebels survive, but are scattered. Many regroup on Dagobah, where the Jedi Temple is currently located. They take what they have left, and come to the decision that instead of having planetary bases, they take their last few ships (2 modified Corellian Corvettes, 2 MC80 Cruisers one of which is Home One, 3 Assault Frigates, 4 Medium Transports, a handful of Marauder Covetters and a handy mix of X- Y- A- B- Wings
The third note is that it's not just Jedi use lightsabers. It is not uncommon for Rebel soldiers to be trained with the use of a Lightsaber, although it is rare to find someone without force sensitivity who can go toe-to-toe with a Jedi in lightsaber combat. As such, anyone with Weapon Proficiency (lightsabers) is assumed to have been given one by a Jedi, so does not have to pay for one. You still don't get the bonuses that Jedi do (like deflection, Lightsaber forms, etc.etc.) but hey; lightsabers. As well as this, it is common for Jedi to join the Rebels to help end the tyranny of Palpatine. You'd think that having Jedi would swing things to the Alliance quickly, right? Well, not exactly. Not long after rising to the throne of Emperor, Palpatine began researching new medical technology, and found a way to give Imperial soldiers force-enhanced reflexes. This mean more dangerous troopers (less likely to bump their heads, and are pretty accurate) so watch out.