Here’s a little different perspective. Picking a litter and a breeder are where you will have some information. If you can meet the parents or related dogs (and for a hunting dog hunt with them) then you will get an awful lot of knowledge. Find a breeder that you trust and write down what’s important to you and give that to the breeder then trust them to do the picking. They know the breed and they will be with the pups for a couple of months as opposed to a few minutes. I find that everyone wants the best dog and the pick of the litter but their definition of best is not the same. I would put the energy into picking a breeder and/or a litter and communicating what you want to the breeder. After that, just consistently spend time working with your dog and you’ll be surprised how they start to fit in to their new pack and try to figure out how to please you.