If you have the room, money, time, patience etc for another dog and you feel like it would be in the best interest of the dog I would say go for it! I know, I have 5 too and I would love to take in another, and we did, a Dal for a couple of weeks. It was so weird how just one more dog could make your life that much more stressful, we have enough space etc but we had a hard time, the Dal just didn't fit in at all. Try it out, if the dog adjusts well to your five and visa versa then I think it would be a good thing...Good luck!