Parenting

There are a whole bunch of minor league team names that are fun. There are teams called the Jumbo Shrimp, the Iron Pigs, the Flying Squirrels, the River Bandits, and all of them have fun logos already available on baseball hats.

There is of course the question of copyrights, but there are three good reasons why you probably don't need to worry about getting sued. First, it would be unbelievably bad press for any major or minor league or team to sue a bunch of tiny fans. Second, you'll probably be buying a bunch of merchandise like hats and banners with their logos on it (assuming you aren't printing your own using their logos). Third, they would probably get laughed out of court at the notion that a multi-million dollar franchise needs to differentiate itself from the sandlot kids in diapers. You're not profiting from the name or logo (right?), and they have better things to do with their time than volunteer to be the villain in the court of public opinion.

Edit to add some more: Trash Pandas, Rumble Ponies, Sod Poodles, Yard Goats, Blue Wahoos, AquaSox, RubberDucks, PaddleHeads, Hot Rods, Cannon Ballers, and the Baby Cakes.