I need more pics, but I don't know if it's a good idea to add group photos or not. Should all my pictures be solo?

Not necessarily. You can add group photos as well as pics of your kids or pets, but solo is preferred as this is you, who's looking for ..

Some members include group photos and they are ok. But keep in mind, that this is a dating site... the other people in the group photo might not want to have their pictures posted in dating sites. So, your call.

Pictures of kids? IMHO (I have to say this because I have been accused and found guilty of forcing my opinion upon others) pictures of one's kids should not be posted on dating sites. There are a lot of predators out there lurking in the dark.

Welcome to Mingle2
and good luck in your search.