The movie could have been better, for sure.
Apart of what I already wrote in this thread about what I consider problems in this movie, let´s talk about Snoke... Not a Sith Lord, but still powerfull in the dark side. An Old being, with a deformed body, but still powerfull, what means that he passed throught many battles and won many of them (and yet, he was never mentioned before).
Therefore... He came from nowhere, and is back to that place again (after a stupid death...). If he was Darth Plagueis, it would at least have been comprehensible and would make more sense in the Star Wars Universe, but it wasn´t Disney´s choice. Now, we "know" you don´t need to be a Jedi nor a Sith to use the Force...
In the next movie, Rey will be a Jedi Master? Luke is dead, and Leia can´t do this. Who will teach the new generation of Jedis (a predictable thing "announced" by the little boy near the end of the movie)?
So, the words of Kylo Ren comes to my mind: "Forget the Sith, the Jedi and all that happened before..."
Let´s hope for a better movie closing this trilogy. But I wouldn´t put my money in risk waiting for this.