So Yeah about Ethel :
IMHO , the perception check is enough, its gives you certainty that Ethel is lying and allow you to avoid killing the two villagers. You might earn a bit of exp for it, though. In Baldurs gate, whenever you unlocked a door, disarmed a trap , you earned a bit of exp. Succeeded dices rolls could gives you exp and that would feel like a reward.
Yet, in this quest, whatever you do the two brother dies . Or at least, I didn't find a way to allow them to survive. And even if you tell their sister that Ethel killed them, the outcome of the discussion is still ''Ethel cage Mayrina and flee''.
So instead, maybe allow for a dialogue with a charisma check or intimidation check to tell the two brother to stay away from Ethel. If they survive, they give you a bit of exp, a small loot item. And maybe they welcome Mayrina when she come back, or throw stones at her if she comes back with the undead, saying she is a monster now. I dunno, just an example. Feel free to give mores.
About Raphael :
Its could probably be solved in a few easy ways as well.
If you draw your weapon and attack Raphael : you could either see a small cutscene where he teleport away from your strike and mock you, then he talks about his offer and disappears. That way the player understand that Raphael is out of his reach for now. Probably the simplest way
Another way is to just make the player fight a very strong Raphael that quickly kill your whole party. THis way, you can attack him, you have the choice but its game ovr. I love this option, but I wonder, if he could do that he 'd probably do it, as it would be the easiest way to get the tadpole. Unless he really wants something else, like a service. so the top option is prolly better imo.
You could also fight a weak/ mediumly strong Raphael. Once you wound him enough, he backs off , threathen and snarl, then say he ll come back. This way the players understand that the cambio is not strong enough to win against him, but too interested in the tadpole to give up
Regarding the ''just do it option''.
This is trickier, but maybe Raphael could say that he need tools to extract your tadpole, or maybe he need to wait for some reason but that he may ask you for a devil pact right now. This pact will give you boons, and promise the tadpole and a service to Raphael, but will give a horryfing disadvantage later in the game if broken, and require a subquest to remove the curse. If you accept the service it might be a very evil thing. I mean, just like Ethel, if you ask her to remove your tadpole something happen, you lose one eyes ! So asking Raphael to do it, even if he can't do right now for some reason, should provoke a reaction. Feel free to suggest more ideas !
