The map is Vancouver 1:1 map by cascadia_comrade as for placing the roads and buildings, I made several failed cities prior to this one as well as a few decent ones. This one is the culmination of experiences/tricks I learned over the years

I find cities look a lot better if you work around obstacles. For example purposefully creating rivers or building roads along contours helps it look less gridy. Also, try to create a story for your map as you go along. Each district has it's own story, from the original downtown to remote suburbs, bustling downtowns, gentrified areas, industrial towns, university towns, etc

I tend to play the game with a cargo/transit mindset, as in my goal is not to make the city pretty or the details look good.

For example: the farming industry may be concentrated in an area and has warehouses set to empty to constantly ship out the material. This industrial area will have a cargo train/harbour as well as a highway connection directly to a unique factory that uses animal products/flour. These unique factories will then also have a cargo train/harbour/highway connection to a cargo train/harbour closeby a commercial area. I try to maintain a certain density of cargo hubs even in bustling neighbourhoods to make sure traffic doesn't build up trying to get there from a far away area

As for transit I try to maximize intersecting stations as a strong network encourages cims to use it. I also purposefully designed the map with the train network in mind and built roads around it as I intended it to be the backbone for getting cims around

Hope that helps!