I think Lilith wouldnt work for a harem, she is very openly evil first time we see her she kills a man by devouring his soul, the dev would need to do a lot of work to convert her to the good side and that would kinda ruin her IMO and i really like her and wouldn't want to see her ruined.
With the many different paths planned it would be cool to have one where everything goes bad for the MC, have one where Lilith plays into his naivety of trusting her too easily and greed/insecurity of being afraid he might lose all the other girls if he doesn't get her help, only for it to come crashing down on his head in the end when she fucks him over.
Most of the endings are on the good side, you can get almost every girl in one giant harem, it be cool to have at least one or two where the MC is just totally fucked because he made all the "wrong" choices. It adds to the overall replayability and also makes the choices also matter. I dunno about you but i have played so many games on here where choices dont matter or make very little difference in the end and that just pisses me off, the complete illusion of choice. I am hoping this game is different and from the looks of it so far
jojozz is doing a great job of it, if i follow the path with the good goddess i should have good things happen, if i pick an evil succubus demon then that means bad things will happen there are plenty of warnings to us as a player so there is no surprise there, simple as.