I think legendary weapons should be able to line up with starforged, not be heavily surpassed by them in-slot. A damage buff to Pigeon's Stare to have it within the same realm as Disintegrator's damage makes sense. It does not have the movement and wind-up debuffs but it adds a challenge to stay on-target. It should be adequately rewarding to do that, but instead, the legendary passive 30% damage only brings it somewhere close to the baseline of a starforged Disintegrator.
It doesn't compete with other high-level beam lasers like the RGBeam or just a standard starforged beam laser with % damage superior passive lines.
All of these pale in comparison to a starforged disintegrator with % damage passive lines though. The raw numbers are way higher.
The Pigeon's Stare should be worth using without the extra damage, and it should feel bonkers when you manage to stay on target long enough to trigger the overload. So for example, I would push the base numbers up by 10%, and have the passive add 50-60% to the damage. This is to bring it in line with a well-rolled superior Beam Laser or Disintegrator. Or, keep the base numbers the same, and push the damage bonus to 100%.