I recently discovered the "Remix" urban design tool that lets users redesign existing streets and intersections like an IRL Cities Skylines. It's brilliant.
I came across it when someone on a local subreddit shared a redesign of an intersection, I was blown away with the results.
Screenshot: https://imgur.com/a/qorZWwg
Remix share link(desktop recommended): https://platform.remix.com/streets/plan/a367ea4b/scenario/f8...
Unfortunately, it appears to be enterprise only at the moment. I'm genuinely shocked they don't have a hobbyist-level free / cheap tier—I'd wager that there are thousands of urban design enthusiasts who would love to use this thing.
OP, you should reach out and see if you can collaborate with them.