Angel Cartel: All types, although mostly kinetic and explosive.
Amarr Navy: EM and thermal.
Ammatar Navy: EM and thermal.
Blood Raiders: EM and thermal.
Caldari Navy: Kinetic and thermal.
Centii: EM and thermal.
Coreli: Kinetic and thermal.
Corpii: EM and thermal.
Domination: All types, mostly kinetic and explosive.
Gallente Navy: Kinetic and thermal.
Gist: All types, mostly kinetic and explosive.
Guristas: Kinetic and thermal.
Khanid: EM and thermal.
Mercenary: All types.
Mordu's Legion: Kinetic and thermal.
Odamian: Kinetic and thermal.
Pith: Kinetic and thermal.
Rogue Drones: All types.
Republic fleet: All types, mostly kinetic and explosive.
Sansha: EM and thermal.

Best damage to do to NPCs

Angel Cartel - Explosive
Blood Raiders - EM or Thermal
Guristas - Kinetic
Mercenary - Thermal
Mordu's Legion - Thermal or Kinetic
Sansha - EM or Thermal