Indy 4 is, without a doubt, an awesome and pretty good film. As an Indiana Jones film, however, it is way to unfocused. Indy becomes practically a member of a ragtag team. That's not how Indy does. And there are to many thematic threads. Indy works best when it mixes two things (ex. the Old Testament and Nazis), rather than a billion (Soviets/McCarthyism, Conquistadors/the city of gold, greasers, telekinesis, crystal skulls, and aliens).
The good news is that Star Wars has always been about a lot of things as once, so if Episode VII falls into the Indy 4 trap it'll still be pretty good. Besides, Indy 4 is only so cluttered because of two decades of rewrites. Looks like Episode VII will be facing the normal amount of rewrites.
On the flip side, the prequels were so disappointing because they faced no rewrites.