Coruscant was one of the cooler parts of Star Wars to me. That and Nar Shaddaa, which is similar but takes any pretense of utopia and swaps it out for Space Vegas and crime lords.

I helped build out a player city setting for a sci-fi MUD that was substantially inspired by Coruscant among at list of at least a dozen other megacities like Akira's Neo Tokyo, The Fifth Element's NYC, Blade Runner's LA, Mega-City One, parts of the real world like NYC and Dubai, and then numerous elements original to the setting including its various alien races. It wasn't a full world-city like Coruscant but it was meant to represent an immense megalopolis of tens of billions on a similarly massive, dense, vertically stratified scale, with all its vibrance and flaws.

It's a really cool premise for a setting and you could make it fantastically interesting and detailed. Making it fully open world is absolutely unrealistic, of course.

KOTOR's Taris setting is maybe a good example. You could see the vast city in the background but there were platforms you just couldn't walk beyond. Or DX:HR's Hengsha, which showed you a depth and breadth but was within the scope of what a video game could contain and deliver.