Could you use Metropolis as a partial stand-in for Coruscant? It's a few decades earlier than you were thinking, but it was also a few decades ahead of its time, so that all balances out. You might want to avoid the scenes with cars and planes (or not), but there's some still shots that are basically hand-drawn or animated by the architect who designed the place.

If you do go with that route, you might want to integrate the old Metropolis stuff with some newer concept art of Coruscant, going back to the high-res scans in the Shadows of the Empire CD. You can use pans and zooms around this material instead of CGI whenever you need an establishing shot of the city. Or is that a little too cheesy?

Also, fake matte boxes and lower framerate for Jar-Jar. (comedy option)