Well, this movie checked off both "good" and "solid story" for me, despite having a lot of action. But most importantly, I feel it told a realistic story within the confines of the Star Wars universe. No, the heroes don't get a happy ending, other than the knowledge that they gave their lives to eventually save others'. More movies need to end like this. This is realistic. Happy endings are rare, especially in desperate life-or-death wars. Most of the time, people just die, often in futility. If the heroes had suddenly been whisked away by a ship, I would have felt cheated. It would have changed the story from realistic to unrealistic.
But the realism wasn't just in the ending. The way the characters acted, the different factions of the rebellion, and the actions the Empire took were all very realistic as well. I actually like the fact that the main characters weren't hyped up with overbearing, overly-individual personalities (aside from the comic relief droid, who actually fit in quite well regardless). They felt more like real people than caricatures trying to sound like real people. Not everyone is super interesting or has some quirk that lets you pick them out of a crowd immediately. Often heroes are just regular dudes put in a bad situation. That's what these guys felt like to me.
There's also the issue of what people are calling "fan-service". I disagree with this term in this case. "Fan-service" implies something superfluous to the story that is only included to give fans a thrill. However, if you look at the things that are called "fan-service" in this movie, in the broad scope of fitting this movie into the timeline, almost all of it was necessary. They were things that would have actually happened at that point in time. To me, it's less about showing it to the fans for fun (though of course there is an element of that). It's more about making the story fit into its place in the timeline. Not including those things would have been strange, because they happened and they needed to be shown. As a non-fan who wasn't looking for any kind of fan service in the first place, I just can't agree with people who are talking about the movie's "fan-service" in a derogatory way or implying it's just fluff.