I'd like to play an VIII spin-off that wasn't a prequel or sequel. Prequels/sequels entail events which revolve around or are somehow related to the development of the core characters (either the heroes or the villains or both). A spin-off is something like the racing games which is entirely set apart. I would say Before Crisis counts because its events are not directly involved with or related to those of the other games in the compilation. While characters may be mentioned, you neither play as a core character nor play any significant role in their history (apparently, a Turk witnesses the Nibelheim massacre, but that's still not a significant role).

On topic: Moomba makes me think of a superdeformed anthropomorphic Red XIII.