[quote=RagnarokCzD
Like when they lured that Drow Male to society where his gender will no longer mean that he is lesser creature compared to woman?
Or like when they lured those Goblins to the same, by promising them riches and power while they will conquer the world?

I dunno, seems pretty appealing to me, we just usualy dont fit their target group.

(from character creation only Drow Male, and maybe Half Drow might be interested in my opinion)[/quote]
Do they actually make that offer if you play as a Drow male? Because if so then that is exactly the sort of thing that I actually want to have exist in this path. And ARE their members in important places? Again, what information do we get that suggests this cult has meaningful reach outside of this area? (his area that I just realized I don't think has a name) Also your mention of them wanting to conquer the world actually bgrings me back to something you mentioned earlier.
"Except they allready control Selune temple, Blighted Willage, and half of Underdark, they succesfully raided Waukeen's Rest and Tollhouse, and are threatening Druid Grove. O_o
Seems powerfull enough to me."
They control a temple that seemed to have already been abandoned and let them just move in, they don't really control a village, they destroyed it, just like they destroyed an inn and a tollhouse, which seems to just have been a place where this one guy and maybe his family lived, from the impression I got. And I don't think we get a sense of how much of the Underdark they control until we actually get there, I at least didn't find any hints as to what they control. As for the druid grove, that ties into a problem less with the path than with the game at large-no sense of scaling. We don't know how powerful druids are and how easy or difficult it should be for them to be threatened. As someone who isn't familiar with D&D lore, I don't really know how daunting druids would be for the group. As you've pointed out, Halsin their leader got captured by them, so why should we think their ability to threaten the grove is especially noteworthy, even on top of the fact their other resistance is in the form of tired refugees. We don't learn anything about the wider world that would help us put the Cult and their threat into context.
Oh and another problem with the game as a whole that impacts the experience of the dark path; we can't actually talk about our intentions regarding the cult with our companions. We can't ever say that we're joining them with the intent to betray them to any of our companions, we don't even get the option. Which weakens the roleplay value to me since the only differene between genuinely joining and joining to betray them is all in your head. And when the option of "join to backstab" is one of the obvious motivations you could have for joining the cult, the fact that we can't bring this up is an issue. One which ties into the lack of ability to talk about ourselves and our own characters in game, thereby solidifying the character in the world.