What are some good questions I should ask, things I should look for?

We have two in mind and one practice has 4 doctors, younger, older, you name it...

and one has just the one doctor, who is old, he was DH's doctor as a kid (DH is 31)

I feel like I'd rather go somewhere with 4 doctors, I can get to know all of them, so if our main dr is off, sick, on vaca, I will know who is dealing with my kid...like what happens with the place with one doctor??? who the heck would the baby see??