Labs are not small. Think 70 plus pounds.
There is no best dog for everyone. It depends on the personality traits that you like, the lifestyle you lead, etc. You really need to take your time. Visit breeders or places where dogs gather. Ask questions.
You say you want to play fetch. An Australian cattle dog will play fetch until your arm falls off. They are bright, one-person dogs. As working dogs, they are not lovey dovey.
They have short hair, which is shed once or twice a year in a brief period. They weigh between 35 and fifty pounds.
Bad traits? They were bred to herd cattle, which they do by nipping at the cows’ heels. This trait needs to be discouraged or they will herd you and your family!