There should be people who can play an instrument to boost other people's stats. There should be diffrent kinds of instuments and a whole new skill that the higher you put your skill in the higher people's stats go up and the better you sound. Of course the materials to make the instrument would affect this also. Also the duration of the instrument should be as follows...Duration played x musician skill (skill + quality)/2
Once you gather enough people you could build a stage and all of the people can play and the effect doubles for all the people around.