Damage type to protect against:
Guristas - Kinetic / Thermal
Serpentis - Kinetic / Thermal
Blood Raider - EM / Thermal
Sansha's Nation - EM / Thermal
Angel Cartel - Explosive / Kinetic / Thermal
Minmatar Fleet - Explosive / Thermal
Amarr Navy - EM / Thermal
Mordu's Legion - EM / Kinetic / Thermal
Mercenaries - Kinetic / Thermal / Explosive
Rogue Drones - ALL Damage Types
EOM - Kinetic / Thermal

Main Damage type to shoot at the enemy:
Angel - EM(shields) Explosive(Armor), or thermal all round
Amarr Navy - EM (shield) Explosive(Armor)
Mordus - EM (shield) Explosive(Armor)
Gurista - Kinetic / Thermal all around
Blood - Em/Thermal
Sansha - em/Thermal