the sidewalk that leads to the house or garage look square while the sidewalk for the street does not, possibly due to perspective distortion.

Some things look beter looking down, because RPG maker uses square tile and the only way to make square things stay square is to look down directly at them. An example can be that girl in the read shirt looks like the image was directly from the side rather than at an angle that looks down on her. I myself prefer to have character rendered at a lower more front-facing angle vs an isometric building.

Things like the sprites are rendered independently, and based on the lack of perspective distortion, each character (an car) look to be rendered using an isometric camera (not sure if that is the term daz uses, or what mode, I use Blender instead). I haven't played this game so I haven't seen how it behaves to know for sure, but my guess is 3 things.