>>716111708My guess is their rationale was to make it so World's would be both its own thing and serve as a "Rainbow Road medley" with the setpieces it uses. Stuff like being in the clouds like Super Circuit, the train they added to 64 in 8, the space station is a fusion between 8 and Super's in a way, it has the long boosters like DS, oversees the city by the end like Double Dash, goes into space via warp star like the ones in Wii. Only one I can't quite pin down is 7's, maybe the river is meant to represent it since you're reaching a different section with theming different from the Rainbow Road itself? Wouldn't mind them adding in some retro ones in an update at all though.