Dear Jorge,
as to the point of compassion; yes, humans seem to be much more cruel to animals than predators (which are animals, too). Sometimes I am taken by the notion that we deserve every pandemic that will ever come up. Carnivores hunt and eat other animals; that's bad enough, but it's the way this universe is designed. It's the sheer quantity of domestic bred animals consumed by a human overpopulation that perverts this whole affair. I could go on, and I know that many of us would go further and draw radical consequences. However - cowhides are used for shoes and even carpets to a much higher amount than for drum heads. And still the hides are a by-product, compared to the demand of the beefsteak addicts among us. We drummers are a small crowd, and most of us (drum set players) do resort to plastic heads already. Using cow skins might even be seen as an expression of a "no waste" philosophy.
As far as ring and overtones are concerned, I'd like to throw in one aspect: Often it's the overtones that give the drum its character, especially in an ensemble, where they really enrich the group sound rather than being perceived as an annoying ring. Overtones also lend brilliance to the attack, which underlines the slap effect. On the other hand, an old skin that has been stretched and tuned up and down hundreds of times, simply loses its texture and vibration quality. It gets near a chamois. That said, I can tell I've been using thick hembra heads for 20 years and more, while a macho will last maybe 5 to 10 years. And if Cuban drummers don't change their drum heads often, it may rather have to do with scarce supply ...
Apart from that, it's probably hard to get any excessive ring from a mahogany Gon Bops drum
Thomas