Yes, I agree, the bigger the bitch, the better. The AKC Standards on the adult Chi weights are anywhere from 2-6 Lbs.
With picking a male for breeding, I would say the smaller the better & yes, have a reference of knowing they can produce small puppies & always remember to check their history also from there Dad's & Grandfathers to see how big they are & if they they also produced small pups if you can.
Usually the pups are born anywhere from 1 oz. to 5 oz.
Heather NW Iowa
No matter how little money & how few possesions you own, a DOG makes you rich.