I'd say that as long as you stay with the Rapoon albums released during the nineties, you are pretty safe. Stylewise they focus more heavily on the eastern influences (raga drones, looped tablas, etc) that were also such an integral part of early :zoviet*france: (who btw are in my top-3 of favorite groups). While maintaining some of these elements, later Rapoon also ventured into dance rhythms and even some (pseudo-)classical piano compositions, which is quite dull to be honest. Actually I haven't heard Errant Angels that Zeno mentioned, but I'd recommend albums such as Raising Earthly Spirits, Vernal Crossing, or Recurring Dream Circle.
Of all the ZF splinter groups, one little dark horse I like a lot is Mark Spybey's Propeller project. There are only two or three albums, that aren't too hard to track down at discogs for example.