If you really want to be an effective ECM guy, you simply focus on blue bots, and about 2/3 of the extensions in "electronics"

ECM has a natural low chance to hit and really high power consumption, so you need:

• "efficient ECM Technology"
  to lower AP usage per cycle

• "Jamming electronics" and "complex Jamming electronics"
  to increase chance to hit

• "Optimized electronic warfare"
  to lower fitting costs of ECM modules

• "long distance electronic warfare"
  since you want to stay as far away as possible

• "Accelerated target locking", "long range targeting" and "Sensor connection"
  since you want to lock your targets faster and at reasonable distances

Additional you will need:

• "nuimqol robot control"
  to get access to blue robots (lvl7 for ewar mech)

• "basic/adv robotics"
  to boost the robot bonus on ECM (lower AP, higher chance to hit)
  decide early if you want to stay in cheap light ewar (=basic robotics)
  or ewar mech (=adv. robotics)

• "Spec ops. robot control"
  to unlock ewar robot/mech and get stealth-bonus

• "Accumulator expansion"
  to increase your buffer AP

• "Energy management"
  to improve your AP regeneration