In my opinion, Malinois should only be owned by serious dog people who will give them a job. A friend of mine rescues them and they are born putting their mouths on something. They are not nicknamed Maligators for nothing.
She calls them cats on crack. They are super active and mouthy. It makes them good police dogs, schutzhund dogs and performance dogs. Not great pets for the average household. I have 3 in my agility classes, great workers, tough dogs.
Agreed. They are awesome dogs, but not for the average owner.
Incidentally,
this is the video that convinced me that a Malinois may not be the pet for me in this lifetime...

Super dogs, but not for everyone.
Same deal with Border Collies, as I see it... cool, smart dogs, but unless you're going to devote your spare time to training, molding, and shaping them into super-dogs, neither you nor the dog will be happy.
My vote is for a big male Collie from a good breeder who has sound, smart dogs. He'd be big enough and easy-going enough to hang with the boys, not so smart that he can't entertain himself quietly, and smart enough to enjoy playing obedience/agility/whatever. As an added bonus, they're not a bad breed to start in conformation with, as long as you're willing to learn to groom and handle correctly.
Leave off the super-drivey agility-all-star breeds for right now. Your friend is interested in doing sports with the dog, but it doesn't sound like she's actually tried any yet. That's fine. Start with a low-key dog. If she loves obedience/rally and wants to really put heart and soul into it, she can get a Border Collie or a Mal if she REALLY wants to.