The biggest hazard with the ladder-style story progression structure is that all the heroines but the 'true' heroine get gypped. Aoi Tori, at least, has the advantage that all the paths are technically 'true' in an alternate worlds sense, but it still feels like the heroines other than Akari aren't really getting treated equally.
In the case of Aiyoku no Eustia, the author failed utterly to create internal consistency, as his setting (both the general one and the heroines' settings) made any path other than Tia's path impossible within the greater context of the story. This is actually a trend with a lot of writers who like to use the ladder-style, where they fail to maintain internal consistency due to a half-assed attitude toward the non-true heroines' stories.
