You are talking NON-SENSE. When people are asking for character development they aren't talking about having these characters entire life story's explained to them, what they do need is some short insight into these characters, interaction with the rest of the cast, and growth. By the end of ANH we know exactly who and what Han Solo is, a carefree Rogue out for a payday. We know how he feels about Luke, he thins he's a dumb farm hick. We know how he feels about Leia, thinks she stuck up but pretty hot. We know how he feels about Obi-Wan, a crazy old man with a weird religion. We know how he feels about C3P0, dumb droid that needs to shut his yap. The same as true of all the other characters. Han Solo grows from being a "solo" rogue out for himself to caring about the rebellion and the friends he's made along the way. You can't get any clearer archetypes and arcs than you do with ANH.
Now, I'll just quote this user:
After all that and what I just typed, how does Jyn feel about Baze? How does Bodhi feel about K2 or Baze or Jyn? Why did Bodhi defect? I don't need a long complicated reason, just something. Why doesn't Machine gun guy not believe in The Force? What caused him to stop believing? What we have with Rogue One are a group of strangers who don't really interact with each other or bond together but decide, for their own personal reasons they don't wish to share, to fight the Empire.
Now, I'll quote myself from earlier:
Do you understand now when people say the characterizations are weak?
I think you're correct, but it doesn't stand out so much as to be a detriment to me. Of course A New Hope does it better. That's why that one movie transformed cinema and a generation of movie-goers.
I enjoyed Rogue One tremendously despite that.