[Suicide Junkie]

Very well, the answers i see:
*Decrease the damage
*Increase the ROF to 2 (IMO best solution)
*Make it more difficult to reach (say physics lvl2, astrophysics lvl1, Energy Stream/Pulse Weapons lvl3)

My way was to remove it as a unique weapon.
Instead, it becomes an "upgrade" for other standard weapons. You get the same weapon properties (ROF, range, size, cost, etc) , but 80% or so of the damage, and a phased damage type.

Phased energy + Energy Stream (APB) = PPB
Phased energy + Torpedoes = Polaron torpedoes
Phased energy + Missiles = Polaron missiles.