Went for as many happy endings as possible.
54/66 good endings.
11
Neutral were:
Sill (she had to disappear later on so that Lia and Maris went from -2 to +2). Didn't kill her, she stayed a cow.
Kanami,
Maria,
Satella and
Kou require a different ending than the creator one, and the latter is better due to Lia and Maris granting two good endings instead of one.
You have to chose between Leila/
Julia and
Shizuka/Nagi/Annis respectively.
It may be possible to get
Kaoru and
Wichita, but that would remove Chizuko and Magic.
It may also be possible to get
Sheila (and lose Rona), but I'm 99% sure you would also lose Hunty, so nope.
Usually,
Sanakia gets her bad ending, since Toushin City has to be conquered (requiered for the creator ending, and it enables Merim who is required for her own, Ruberan and Mills ends).
However, Toushin City got taken in the Creator phase by happenstance and it seems to remove Sanakias bad ending flag. So I got one less bad end due to a bug.
The sole bad ending is
Annis, though you could swap her with Shizuka. If you save her, you lose Shizuka. With the two of them and Nagi, you always get at best one good, one neutral and one bad ending respectively. It may be possible to prevent Annis/Shizukas death by only battling Zeth once its taken by monsters, but it would remove too many events and other happy endings. No bad ending should be possible by ending the game at an earlier point, but you would miss a ton of good endings, obviously.
Getting as many bad endings as possible may also be funny. Unless I miss something, one would end up with around 61 bad endings, 4 neutral endings (Kou, Shizuka, Kaoru, Satella) and one good ending: Sill. Man, this could be the ultimate Rance ending.