This or That?

If the breeder says the black and tan produces pups with stronger drives and personality, and you are concerned about the stronger drives and personality, go with the other bitch, but...

that is only 1/2 of the equation. Maybe not an entire half, though it is half of the genetics, you must also consider the male.

It would be best to compare the male to the female, their temperaments and traits as well as structure. Color is the last thing on the list to consider.

Do you want a dog that looks like everything you dream about?

Or

Do you want a dog that acts like everything you dream about?

You can get both, but if it is a question of one or the other...

But, I also think that much of the dog's personality has to do with litter standing as much as genetics. Not every pup in a litter will be super independent, or hard, or pushy, or competition-material. So it is important to work closely with the breeder and maybe even visit the litter two or three times while selecting. Maybe do some temperament testing on the puppies to get a good idea of their character.

Just because you see a puppy tackle and "dominate" another puppy does not mean that it is dominant, in another ten minutes the other pup may do the same to him and more. But if you look at the puppies a couple of times a week or so between, you can get a feel for which puppies seem to be the leaders and which are more followers, which are outgoing and which trend toward being less so.

Drop your keys so they make a noise, discover which pups recover quickest and how they do so. One might bark and try to investigate, another might take the keys and run with them like a trophy, another might bark and stay away, another might totally ignore the incident.

Crackling a plastic bottle is another thing you can do. See who is interested, and what they do. Who gets the bottle away from the others the most often.

For a first pup, you really want a middle of the road puppy, a puppy who is not likely to run away at a sound and stay away, but also one who is unlikely to get the bottle every single time. You will not want a puppy that totally ignores it. You will probably want a puppy that joins in the play, notices the sound, ok to startle so long as he recovers quickly.

Good luck.