I'm impressed that you have the whole family working on it. We started out that way (my wife, 8 year old daughter, and 6 year old son) and we hit a jackpot early on (58 silver halves). After the first two skunks, I lost all my family labor. They still listen to my excitement over a buffalo, silver dime, or a 1918 King George, but I think I am on my own for now.
The missing FG's are called grease errors and need to be completely absent to be valuable. I think a raised bump has some value, but just missing the G or the FG being really light are not worth more than face as I understand it.
I am mainly looking for silver but since there are so many skunks it seems like you have to look for something else to keep it interesting. Best of luck!