Here is a little challenge, but, please note, if you take it up and reply with a comment, I am off-line for a few days, so publication of comments will not be till later in the week:
In Luke's Gospel (and in Luke-Acts as a whole) there is an obvious acknowledgment of the reality of the Roman empire woven through the undisguised story of a new movement, replete with a head called Kyrios, which grows from nothing in Galilee to something with a presence in most towns and cities of a significant portion of the empire, including Rome itself.
Is Luke's Gospel:
(a) an attack on the empire?
(b) an apology for the (non-threatening) kingdom of God?
(c) a presentation of an alternative kingdom to the empire? (In what sense is it an alternative? What are it's long-term ambitions?)
(d) none, some, or all of the above?
(I am working on a presentation on Preaching through Luke's Gospel in 2010).