Octorox said:
Here's some Ralph Mcquarrie Coruscant art.

http://www.sithtower.de/sithtower/blue/index.php?title=Coruscant&file=coruscant

Honestly, I doesn't really look much different than how it ended up in the prequels, same with Aldeeran. About the Jedi robes: how would you explain why Yoda, Ben and Anakin all wear Jedi robes as ghosts in the end of ROTJ?

Obi-Wan wore Tattooine farmer clothes like Owen. That much is obvious. I figure that Yoda made his from some material he had hanging around after his original clothing wore out on Dagobah perhaps. Or perhaps to set Yoda apart he always wore some basic scruffy robes. And Anakin appearance shows how he's in harmony with them. Like how he would have appeared if he stayed on Tattooine to farm moisture with Owen (brother/step-brother/whatever).

Plus it makes sense that Luke's attire in ROTJ was based on what the Jedi wore except more minimalist.