I don't think it's too much to ask to make a really great Star Wars movie this decade. I just don't see it happening.
I suppose it depends on your definition of a really great Star Wars movie. One of the biggest elements that made 1977 Star Wars great was the special effects. It defined a whole generation of films and started the most impactful special effects company of the century. Judging on special effects and cinematics, we might already have a great Star Wars movie this decade. Or perhaps you want to look at gross revenues. There isn't a studio in the world who would turn down the success of the last two movies.
It's all relative, really. Will a Star Wars movie ever win a major critical award? No, it hasn't defined a generation of movies since the original trilogy. Star Wars was never targeting the adult audience either, from the original to the latest to the special shows aired on TV over the years. It targets a younger audience and always has, whether we like it or not. In today's world, if you want high fantasy to tread new ground, it has to be gritty, shameless, hold nothing back, and be as adult as possible. Neither Lucasfilm nor Disney has ever been known for pushing the boundaries of morality in film.
That being said, who here wouldn't want to see a pre-quel with the hero being a roguish smuggler type who isn't terribly bright but makes up for it with balls the size of the Millennium Falcon, enjoys carousing with the ladies at any hive of villainy and corruption, will do just about anything for money, and always shoots first, yet ends up going up against Vader, who is taking personal glee in systematically massacring any and all scumbag aliens, criminals, and force sensitive children leaving nothing but carnage and sorrow in his wake? Of course for it to be "great", it would have to be bordering on unrated because of language, violence, and sex, and in the end, Vader would win, violently beheading the would be hero at precisely the point where you thought he was about to save the day. I would buy tickets to see it, particularly if they added in some snarky humor and enough bad-assery to satisfy any man's desire for virtual testosterone.