Back to the issue of character development and Sci-Fi...
I think it really is all about the writer. A good writer can develop any genre into something captivating and interesting all the while developing characters with some depth and complexity.
Personally, I read a wide variety of books and will readily admit, for that reason, that I limit what I read to those few authors in each genre who I find exceptional. The "so little time, so many books" concept at work. In the area of Sci-Fi, one of my favorite authors is Robert J. Sawyer. Read any book of his and you will find that the story is clearly driven by the characters, not the other way around. Robert Charles Wilson is another author in that vein. And they're not alone. I find it very hard to believe that anyone could read their works and not see how well they handle character development.
I believe that it really comes down to the old 10-80-10 rule. IMHO in every genre, 10% is trash, 80% is mediocre, and 10% is exceptional. Sci-Fi is no different. Some people, I think, have a lower opinion of the genre than is realistic. It gets painted with much too broad a brush stroke. Some reasons why that might be true:
1. Historically Sci-Fi has been looked down upon. This comes from the early pulp novels and the early formulaic novels that started the modern era of Sci-Fi. That opinion gets passed down generationally and ignores the growth of good writing in the field.
2. Movies typically do not do the books justice. This is true in every genre, but is especially true in Sci-Fi. More people see the movies than read the books and this affects pop culture. Ensuing discussion drives a certain amount of the general opinion of Sci-Fi.
3. How many of you have felt uncomfortable at some point in your life because you were carrying around a book with an obvious Sci-Fi cover (Kindle resolves this dilemma a bit)? Public perception, driven in part by 1 & 2 above, make it hard for people to enjoy Sci-Fi in the same way they would enjoy popular literature or mysery, or adventure or a West Texas Chicano action story.
So, IMHO, Sci-Fi gets a bad rap. Sci-Fi can be, and often is, very well written. Overall it is no better, nor any worse, than any other genre. It just carries a bit of reputation baggage along with the name.