Can it be done properly?
1. What is the storyline going to be? The most popular thought I've seen, is that we get a TV show about Vader hunting down the Jedi. That could get boring however. (Hey, look, he just killed another Jedi.)
2. Will SW actors be used? Obviously, if its about Vader, you don't need Hayden, because you can have anyone in the suit. But then you need James Earl Jones. Anything else will not be right.
3. What will be done with EU? Will Lucas throw it completely out the window, or will he embrace part or all of it? The more scripts he writes, the more conflicts can arise.