I'm interested in finding out the nature of the electron fluid in 
   itinerant systems that are near magnetic  QCPs. The following 
   questions interest me:

   (1). Can spin-fermion models describe at least few "good" materials 
   such as CeNi2Ge2 which seem to show spin density wave type of QPTs? If 
   so, what are the theoretical tools for doing controlled calculations?

   (2). For the "bad" materials, those that don't show spin density wave 
   type of QPTs, clearly one needs to worry simultaneously about Kondo 
   screening and magnetic ordering tendencies. What is a minimal mean field
   model that captures these competing effects?

   (3). How to use conservation principles such as Ward identities to 
   distinguish scenarios where the Fermi volume changes discontinuously
   at a QCP.