I thought that it was pretty solid and entertaining, finishing upper mid-pack compared to all of the previous installments.  I don't think that its fair compare this to the original 3 movies since its been 30 years, the genre is pretty much established, and we know where the overall story is heading.  Capturing the glory of the original three is going to take some big chances, and likely a PG-13 rating, which will never happen under Disney.
Its important for a Sci-Fi or space fantasy movie to follow the rules of the universe that it created (Star Trek used to be the master of this), which this more or less does.  Yea, it was lame that the Imperial ships could barely keep up with the rebels, but this is something that you asked to blindly accept since it was a major plot driver, go with it, or sit in your seat all pissed off.  Lea finally using the force was a little lame, but since she's the daughter of a Sith Lord, not entirely out of left field.  I agree that BB8 is cool, and wish that they would bring C-3PO back as the witty comic relief.  Instead they used the penguin-chickens for that, a few seconds at a time.  At least one of them almost got eaten.  The crystal foxes were a necessary plot element, to show the rebels where the exit was.
They could have made this shorter, but I think it would have made the story even more disjointed.  The purpose of Finn's wild-goose chase (complete with bullshit political undertones) was to introduce Benicio del Toro's character (who I wish had more screen time), and a necessary plot element to the next movie, that we saw at the end.  The battle scenes were pretty solid I thought, although Ren killing his master could have had a little more tension built into it.  Ren developing into his own villain is a nice touch also, avoided being derivative.  Overall, I don't see how this goes beyond one more installment, since like Game of Thrones, the plot doesn't have many more places to go.