I understand what you mean (I had 900 hours into Guild Wars 2). I understand everything you're saying, but I want to make these two points first: 1.) The Prowler will always have superior AI compared to the Vanguard or Magrider simply because it has two barrels. 2.) The Prowler does have strong AV potential; the only reason the Vanguard beats it is like you said, because of the shield. I would actually accept the shield being reworked but the Vanguard itself would need buffing to compensate, not in the AI area, but in the AV area. Without the shield the Vanguard itself is completely outclassed by the Prowler.