I agree that the evil path definitely needs more work. The most baffling part is how none of your companions, the companions who are supposedly the evil ones of the game, are in favor of it. I honestly think that having a companion that's in favour of the Absolute path would make it at least a bit more reaosnable as a path to go down.
We are still missing some tho.
Maybe this will get resolved in the future?
Sure, it's easy to say your character wants to join up with them and stab them in the back when they get an opportunity, but to what end?
Depends on your own character ambitions ...
Since we are only talking about what would be your motivation ... the only limit is your own imagination.

Its the simmilar situation as Gale suggests with Raphael, he also believes that he can outsmart him in his own game.

And that is exactly the case here aswell.

Play along until opourtunity emerges, and then simply GRAB IT.

Also i dare to say that the same question should be asked for other option (killing the Goblin leaders) ...
What end are we hoping for there?
Sure, you help few civilian refugees that you possibly not even see for the rest of your life.

But unless you explore whole Goblin camp (wich kinda can require some small metagaming ... or just really strong dedication to THAT quest.

) and save Halsin, you have no ensurance he is even alive, nor if he will be able to help you (funny enough, you dont have ensurance in this particular topic even if you save him, whole Grove, kill litteraly everyone in Goblin camp and redeem Kagha.

but ofc, you dont know that when you are deciding what to do)
What do we actually know the cult has to offer us?
Well ... It depends:
- If you are Drow Male, cult can offer you a new society where you will no longer be taken as something lesser, just bcs of your gender ...
Same goes for other "often enslaved" races, as Deep Gnomes ... or maybe Goblins if they will be included ...
- Protection against ceremorphosis ... after all, every True soul is tadpoled as we know, yet nobody is changing ...
- Favour of new deity, that seems to be quite powerfull (concidering our encounter with her voice in Goblin Camp) ...
- Ensured good status in this new cult ... since so far every True Soul we met had some local leader position ...
- Raids and looting (its vague reason, but can be motivation for some people) ...
And as mentioned abowe there are few things as:
Contacts between Zhentarims ...
Military power (even tho not exactly the best, but still at least some compared to civilian refugees) ...
Allready gathered loot ...
Beer ...

No one else knows about the tadpoles so their usefulness as solution there is dubious.
That is not exactly true ...
Why exactly would they "need to know about tadpoles" ?
I dare to say they dont.
They obviously have it ... they obviously are using it ... and it obivously dont change them ...
Therefore all we need to learn from them is (quoting Astarion) "how to control it".

And since they do that allready, we should be able to learn that from them.

Maybe this is a path for a player that can say "what if?" but there are just so many what ifs and so little solid facts to ground ourselves in. There's vague indications of higher-ups that you could find, but again, it's all vague.
It have to be vague, once you are choosing between two crystal clear options its no longer "what if" ... then its set if A then 1, and if B then 2.

I believe siding with Goblins is suppose to give you potential, not promise of anything specific ...
You either are willing to risk it, or not. No other option is acceptable.
