anieman and others having the same question.
I will not try to give you numbers but I personally tie with grade 3 capes and saddles. The dry fly quality is as good in a #3 as in a #1, just more flys can be tied from a higher grade.
The size range in a #3 runs from 28 on up to quite large. I tie a lot of size 22s which I like to fish. (can not see well enuf to tie smaller)Tying for my personal fishing I find I can tie a long time from one cape, #3. There are far more hackles in each size than one would expect. In all honesty I feel at the regular price a grade #3 is a "Best buy for the $$". At our year end sale you can not beat it I assure you.
Unless you are tying commercially a grade #3 should suit you well for the sizes you are looking for.
I have taught myself to tie two flies from each hackle.
This is of course not on heavily hackled flies. Still, a bargin and many tiers stear away from the grade #3. I could understand this 10 years ago. Today the development of our genetic flock has made even the grade #3 one of the best.
Give one a try and you will agree with me I am sure.