I don't know of a rating system, but I can speak from my own personal experience. I had to try many different brands, styles, and sizes before I found the ultimate shoe for me. And I tried all the high-quality brands. Each brand, and even each brand's style, is designed a little differently, so what is best for one person isn't necessarily the best for another.
Sad to say, but I've spent about 7 years experimenting to find the best shoe for me, and tried all these different brands:
Freed (tried one style)
International (tried four styles, and two sizes)
Werner Kern (tried one style)
Capezio (tried two styles, and two sizes)
Supadance (tried two styles)
Dance Naturals (tried one style, and two sizes)
Diamant (tried one style, and two sizes)
So I've tried over a dozen different brand/style/size combinations, and have finally found shoes that I really like.
I highly recommend all the brands listed above *except* Capezio. I didn't like Capezio because even though they are much less expensive than the other brands, they wear out and fall apart much faster.
I personally think the best shoes are Dance Naturals, but they are very soft through the shank (arch) area when you buy them. This is great if you have very strong feet and want and need the flexibility. But if your feet aren't strong enough, there won't be enough support and you'll roll to the outside. I last tried wearing Dance Naturals about a year and a half ago, I want to try them again because my feet are a lot stronger now.
Right now I'm wearing Diamant. They are the shoe that fits my foot shape the best.
Other people like Supadance the best, others swear by International. It really does depend on which brand and style fits your own personal foot shape the best.
Good luck!