Regarding Wava, I had thought that returning a bowl of magic water to her was the quest that freed the twins, but it is actually freeing the bird which I had already done by that point and I think I would have found out if only I checked my journal. I suspect that returning to the fountain of pure water would have de-parroted my knight, but I ended up going back there anyway after re-loading to fetch the other water in case it did something anyway (not much).
Aside from that, perhaps I have been exploring the wrong dungeons so far but there does seem to be a lack of bows better than the Dark Bow, I think I picked that up many hours ago and even the legendary bow I found from a miniboss on the overworld of the large island across the sea isn't a tempting replacement. I was almost temped to recruit the assassin at the "evil castle town" just to pinch his +3 Dark Bow!
Viewing post in Bylina - Lure of the Sorceress comments
While most quests have slavic origins in the game, this particular one is based on a spanish fairy tale. It may contain some spoilers if you ever plan to replay the game.
You might be right about the bows, the Dark Bow is devastating, and available relatively early. Just keep in mind that toughness affects resistance as well, so as long as you have it equipped, your archer is more vulnerable to enemy spells.