Interesting survey! I'm reading other people's answers here with great interest. Out of my lot:
1. What percentage of cats do you think would be classified as alpha cats?
Out of four, two of mine are alpha. It took me a long time of reading Hissy's descriptions here of the alpha dynamics before I realised there were two and I began to see a little of what's going on. The raggies are very much 'pack' cats, they are emotionally very close and sociable, and it's rare for any of them to act much alone, while Vicket is very aloof, so it's a case of three and one anyway. Vicket is the alpha alpha, with all deferring to her over food and territory, and backing down instantly if she asserts herself- although two out of the three raggies are twice her size. Jake is also an alpha and the leader of the raggies. He and Vicket share some of the top alpha traits out between them which is very interesting to watch. Over the years, looking at cats who have classic ALPHA stamped on their personalities as opposed to the cat who becomes dominant in a group, I've had three out of approximately twenty.
2. At what age do alpha cats begin taking control of their environment and start ascending to their natural position?
Both Vicket and Jake had alpha personalities from the day I first met them. Vicket at six weeks of age, tried to beat up a yorkshire terrier that she didn't approve of, and a six week old kitten in a serious tantrum is quite mindblowing to watch, we nearly re named her Buzzsaw. She has always been the one, from a few months old, who decided when and how a new cat integrated into the house, and it was on her terms. She has a fair amount of aggression as part of her personality. Jake is a large, friendly clown without any aggression at all, but was ruling the roost over three litters of kittens when I first met him, and he was driving his breeder crazy by being into everything and totally fearless, and by his strength and skill at play wrestling, which he used to deal with any kitten that challenged him. Or any that he felt like. That continued at home. He has never seriously fought, attacked or hurt anyone and it's entirely non aggressive, but he wrestle plays with the other raggies and wins hands down every time.
3. Are there more female alpha cats or male alpha cats? (Any idea of approximate ratio?)
One female to two males of the serious serious alphas as I mentioned. Although I've tended to have more males than females, and introducing Jazzie to this group was a big risk and I knew it: I took it as the raggies tend to be very laid back and easy going and I knew wouldn't challenge her. For ten years I kept the group with Vicket as the only female.
4. Does anyone know what happens to aging alpha cats?
Vicket currently behaves as though she's having a midlife crisis and needs hormone replacement therapy. She will be alpha in this group all her life, she only has to growl and all three back straight off, she never actually has to physically challenge for anything. It's sheer force of personality. If she isn't able to get to the height she wants or she gets too crowded by the others she gets extremely grumpy and short tempered with them, and she has to be fed on the counter while the others eat on the floor, or she will defend all four bowls and not allow the others to eat at all. I can see when she's elderly that I will need to enable that physical dominance more for her in order to keep the peace. Of the other three, Jake eats first, the other two have whatever he's not currently eating, and they change bowls a lot. There is absolutely no fear involved in that relationship. The dominance is seen a lot in grooming, playing, simply deferring to him, but the other two love him to bits. If one of them is unwell or scared, they go to him and that's when you'll see him groom them. Since its a natural part of Jake's personality too, I can't see it changing as he gets older. What would happen if I brought another alpha personality cat into the group I don't know.
5. In your opinion, what is the biggest misunderstanding most people have regarding alpha cats?
The genuine need to co operate with the ranking order? Things like feeding on different levels and providing high places. My gang don't worry or react to you petting or lifting up one of the lower ranked cats first, but that is something I keep an eye on. Incidentally, Jake, who is a cuddle monster, does not DO being picked up, apparently it's undignified. He gets on me on his terms when no one else is looking. Vicket, when she wants a cuddle, stalks up to me and growls at anyone else in her way, and they all clear out on the word, giving her immediate access.