It's so nice to hear though that you don't want one too small! I think that the practice of trying to breed tiny "teacup" dogs actually harms the breed. Of course that's just my humble opinion.
It's so hard to guess what their size will be. I have a friend who's Yorkie is 11lbs, and it's parents were 5 and 6 lbs. Even a vet can only guess the weight a puppy will be all grown up. Initially my vet estimated my Eury was going to be 6 to 7 lbs, and since then the estimate has changed a few times. Her current estimate is 3 to 4 lbs (based on the fact that she is almost 5 months and about 2 lbs).
Good luck in your search and I hope you find the perfect "little buddy"!