I could go either way on that. It does sound like a cool idea to se Coruscant (as long as Palpatine is shown from the back only) and would tie it with the PT more. As long as it also doesn't have too much of a ROTS feel to it, it could really work in the context of the movie.

On the other hand, I feel a bit apprehensive about showing Palpatine in the flesh before ROTJ. I'm so used to the gradual revelation: mentioned in ANH, seen as a hologram in ESB, and finally revealed in person in ROTJ. But maybe I'm just being nostalgic and should look more objectively on this? Very possibly.