When I look at descriptions of the breed, it encompasses everything we were looking for. When I look at the TICA breed standard it goes into great detail about the wrapper but is remiss in stating what makes a Savannah a great pet and companion. Perhaps that's simply because you can't easily judge personality or how playful a cat can be. You can do all the things like measure their tail, see where their ears are aligned and make sure they don't have any rosettes, but if that's what I was looking for I could probably commission someone to sculpt and paint a perfect one to place on my mantle.
I agree to some extent, the personality IS more important in a pet than its looks... actually for me it is more important in a breeding cat too!
Yes, the Breed Standard deals mainly with looks, and these traits will be the same whether the cat is in your home or on a judges' table, but I guarantee with ~90% of cats their personality won't be! The show hall environment can turn confident kitties into scared ones... and you hear owners say "but they're always happy at home"...
We do state in the standard "The ideal Savannah is to be a confident, alert, curious and friendly cat." You are correct it doesn't quite encompass what makes a Savannah so great...but then you have to LIVE with the Savannah to truly understand that. And I do think it great (and preferable) when a breeder can discuss the individual personalities of their kittens and try to match that with your needs in a pet. It is definitely something I've always thought important, and will refuse a sale if I think the kitten not right for that home. My very first litter I flat out refused to sell the folk that came to see the kittens and chose one of the spotted ones (there were two spotteds and two marbles in that first litter), but I knew even at 8 weeks of age (when they first met them) that that kitten was going to be way too rambunctious for their household with a baby on the way and a toddler. I convinced them that the other spotted kitten was much calmer and patient. That kitten is now the cat you may have seen on Cats101, Mondo, the one with kids running after him shouting "Mondo, Mondo"... the livelier one went to live with a couple Chausies and did great too.
And personality can be influenced by the home they go to, a loud and noisy home can turn a kitten into a shy and timid kitten in no time. I saw that once, I had to go retrieve a kitten for another breeder. Poor thing was terrified by the screams of the toddler, yet after a day in a room of my home he was happily crawling into laps and playing. So definitely, not something that is easily written up and judges...hence cannot be in a "standard".