Should i get another dog or puppy what type?

i am 18 and my boyfriend is 23 we currently have a gsd pup 6 months female and even though e are at home most of the dog either one of us or both it seems she may get board as we dont have the energy or time between house work ect to run around the garden for 6 or 7 hours (our garden is a field it mive and totally secure) she has loads of toys to entertain and we do play fetch and hide and seek and tag with her for bout 2 hrs a day would she welcome another dog or feel rejected if we got one i so confused as lu-lu is technically my boyfriend dog allthough he bought her for me i would like to do the same for him but what breed could handle a gsd playfullness