No one will be crossing 8 different heights by design (and they certainly won't be walking down the centre of the Rapidway). If they are, they're crossing at a spot that is not a designated crossing. I don't know what the design is, but the platforms seem to be all poured as "standard" with ramps at both ends. On King at the Hospital, the South end of the platform is how you'll get to it, from the pedestrian crossing at the road there.
At the North end of the platform, it'll probably (hopefully?) be like what's done in other places, where there is a railing or fence that discourages access from places that people shouldn't be crossing:
At the North end of the platform, it'll probably (hopefully?) be like what's done in other places, where there is a railing or fence that discourages access from places that people shouldn't be crossing: