Maybe because I've been searching for answers, but got to the feline diabeties web site http://www.felinediabetes.com/diet.htm
There's a link to nutrition charts, that includes % protein, fat, & carbs, and calories for most higher end cat foods. Charts for dry and wet are separate.
I'm a data junkie, so having the data makes me happy. Now if there'd just be a chart on taste....

And I'll have to remember Mimi's suggestion to get them jerky treats next time I'm at Petsmart for their chewing and teeth cleaning pleasure. Thanks Mimi!