LionsLair: *nod* i even started to make a little program which would create those lists automagically .. but it got a bit stalled :)

the variants are definetly different
mostly they concentrate more on a specific aspect of ordinary bg

crowded and race more about building, race from the start, crowded from a specific point .. hyper is more about aggressive play and counting the chances to succeed or be hit .. nack is a bit more about the backgame than ordinary bg

but then again i am not a pro .. i only play this game for about 2 years .. and almost only on this site :)