I do not think one ripped off the other- I do think though that Babylon 5 showed me the station I had hoped DS-9 would have been. DS-9 was conceived as a busy place with aliens visiting all the time, getting their ships fitted with equipment which would allow their passage through the wormhole with no harm (original story writers guide). Even without the equipment fitting, DS-9 looked empty- rarely did we see ships docked with it and few aliens wandering about- the time we saw anything like that was mostly because it was essential to the story. Babylon 5 looked like LAX in comparison.