I agree that Disney has done good with Marvel and so far with Star Wars. The thing that surprises me about Star Wars though is I am not sure if it is beneficial for them to go backwards in time to do movies about Han Solo and stuff. I expected them to do a lot of spin offs and universal plot webs starting with episode 7. With Marvel, you have different story lines across many characters that are all leading up to something with the infinity stones. So far with Star Wars, we haven't gotten that web yet and it looks like anything like what Marvel has is at least another 5 years away.
While I will probably watch all of these movies, the Marvel universe is more exciting because of how big that story web is across all movies.
I get why Disney is doing it, because they know people love episode 4-6 and hold it sacred, and therefore, they can make money off of it.
I believe Disney has done a good job with both properties. But while we all enjoy what they have done with Marvel and so far with Star Wars from Lucas Films. Lets not lose sight of Disney's goal here which is to make back that $4 billion they paid George for the rights to his properties, and then to make a profit after that. $4 billion is a lot of money, that is why they will use the past because people are invested in Han Solo, and other characters that we already know. Episode 7 and forward will introduce new characters that will hopefully give rise to the web you mention. Also when they started with Iron Man, there was no web, just Iron Man. Once that took off and they got creative people together they will able to put together a string of events and weave the characters into the movies.