Interesting choice, but I think the mysterious feel of the opening sequence is spoiled somewhat by the immediate introduction of Luke. To leave the audience hanging, if only for a moment, works I think.

Also, here's something I brought up a while ago. C-3P0 chattering away during the carbonite scene. It's always bothered me. First of all, he's chastising poor old Chewbacca excessively whilst far more important things are happening around him and he then (rather redundantly, considering we've been told as much by Boba, Vader and Lando) explains that Han will be well protected if he survived the freezing process. His chirpiness is in-character and humorous in other scenes, but here it's just distracting. I'd much rather soak up the emotional severity of this moment than have it ineffectually narrated by 3P0.

That's just about the only thing I'd personally change in Empire apart from some visual alterations.