Typically those megastructure concept are supposed to be built around a physic constant or a known orbital mechanic, with the idea that Physics explain and justify their shape and size.
Like how a Ringworld is shaped, sized and rotating because centripetal force require it (but doesn't HAVE to be scaled around a star, only to be ring shaped).
However this "rungworld" -as you say it- have no particular reason to have this size.
In practice this could be a set of much smaller O'neil colony built like a ladder hence the "rungworld" part, but only end up as a rung if you kept doing this around an entire orbit (point where I will remark that a small moon would be far preferable)
I'll still have to check for the impact of TIDAL FORCE on such a structure. I fear it might slow the rotation of the colonies but I could be wrong on that.
Now for the truly fundamental error:
If I'm getting your picture right, spaceship would definitely NEVER enter a spinning colony by a hole in the rotating parts, and (if that's what you hope for) centripetal force won't keep the air in, quite the opposite.
Also the whole point of linking together several O'neil colonies together is to share the same "static part" which would contain any trading (without using any spaceship) and still host any needed spaceship dock (since it's static).
In any case, that's not on any list of megastructure concept I know, or rather, it's 2 of them scaled up beyond reasons + what look like a critical error.