1.) The Speaker lost his innate ability to speak to the traveler early on, and had to wear a special mask which was destroyed in the Red War. If someone can speak to the Traveler, they may not know it, so there might be a possible Speaker that we haven't found yet. Although the Traveler has been much more active since the Red War. 2.)The Cabal have no concept similar to human beauty. They have lost the need to procreate with the cloning process, although many do anyway. (Caiatl is a naturally born Cabal being as far as we know.) The Cabal value strength as the primary criterion for an attractive mate or comrade. (Hence why Caiatl is very impressed by Lord Saladin's and Zavala's military prowess. 3.) It is possible that Osiris could gain another ghost, but not Fynch really. Fynch's bond to his Knight must be severed for him to take on another guardian. This would likely be done by soul absorption with something like Thorn or possibly the Heart of Oryx. Either might work for such an exorcism.