I've had all kinds of dogs during my lifetime. Beagles were my favorite single breed dog, but they're barking little things. Labs are cool, but too energetic and I haven't had a yard big enough for them in years. German Shepherds are ok, but not my kind of dog. Blue Heelers are awesome. Best dogs I ever had were mix breeds though.
Right now I have a 7 year old Miniature Pinscher named Sophie and a 3 year old French Bulldog/Yorkie mix named Jasper. They're pretty cool, except I think Jasper is retarded. And he marks a lot which is a male thing since he's not fixed and I HATE it...Mostly they both just lay around and sleep unless you're ready to play - Soph is a bit older so she leaves that up to Jasper usually.
Sophie (Min Pin) is VERY protective, and HATES strangers (especially men) and has bitten the mailman before, lol. But if you don't come aggressive and allow her to sniff you a bit, she'll be all up on you to be petted and friendly. When we got her she was so small she was in a little girl's shirt pocket - no lie. She was TINY.
My dumb dog Jasper is all about playing and barking - Soph has taught him to go ape **** when the doorbell rings or if a bird flies by the front door. Yapping little thing. He's cute though - with the brindle marking, he always looks worried and he's very loving. He picks up on things in a hurry, so I guess he's not all that dumb. The only thing that's bulldog about him is his front legs bow out when he sits.