R=regular shot
S=stun gun
G=glue
N=nullwave.
Approximate power increase over regular shot is in parenthesis.

Golden Gun
R-19
S-29 (+50%)
G-38 (+100%)
N-24 (+25%)
N+S-36 (+87.5%)
G+S-57 (+200%)
N+G+S-71 (+275%)

Shotgun
R-81
S-88 (+9.1%)
G-81
N-91 (+12.5%)
N+S-108 (+33%)

As you can see, some of the damage bonuses weapons get from debuffs can get quite insane, and you can even stack them. Ironically the shotgun gets zero benefit from Glued up foes, but stun+nullwave+gloo a Phantom and your pistol gets a nearly 300% damage boost on its shots. Very interesting imo! Thought I'd share.

NOTE: some closing notes from the guy who gave me this information:

    So incapacitation isn't a universal status, but multiple cases that depends on what inflicted it and what's being used for damage (with the general rule being the 'harder' the disable=more bonus damage). Golden Gun (and likely Pistol) gets much bigger boosts than the Shotty and they all stack multiplicatively (note: Glue needs to be applied after Shock/Nullwave). Shotty doesn't seem to benefit from gluing (just knocks things right out of the status), however using Null+Shock gives a greater damage boost than simply multiplying the base statuses together. I would imagine the Q Beam is similar (no bonus from glue, but a bonus from stunning). Also, glue seems to break based on hit count (3 bonus damage pistol shots), but Shock seems to hold for its full duration, so you can ram more damage down. Guessing the intention was that pistol+glue would be the cheap method while shotgun+shock would be the higher investment power option. What I wouldn't give for a mine gun to exploit glue. Obviously need to run more tests with more damage sources against other enemy types.


Weaver
Pistol
R-19
S-29 (+50%)
N-24 (+25%)
N+S-36 (+87.5%)
N+G-48 (+140%)

NOTE: You can apply Glue after Nulling them (Shock doesn't work though). Using a disabling status to setup glue seems to be consistent for many enemies

Shotgun
R-98
S-122 (+25%)
N-110 (+12.5%)
N+S-131 (+33%) <-Not sure about this one.

Q Beam
R-24
S-17 (+40%)
N-20 (20%)
S+N-14 (+70%)

Voltaic Phantom
Pistol
N-19
EMP Grenade-24 (+25%)
N-24 (+25%)
EMP Grenade+N-24 (+25%)
G-38 (+100%)
N+G-48 (+140%)

Shotgun
R-98
N-110 (+12.5%)
G+N-110 (+12.5%)
CF-122 (+25%)
CF+N-138 (+40%)

Q Beam
R-53
CF-53
N-43 (+25%)

Etheric Phantom
Pistol
R-19
S-29 (+50%)
N-24 (+25%)
G-38 (+100%)
G+N-48 (+140%)
G+S-57 (+200%)
G+N+S-71 (+275%)
N+S-36 (+87.5%)
Psyshock+S-36 (+87.5%)
N+electroshock power-36 (+87.5%)

Shotgun
Same as the Weaver, though I saw N+S hit for 141

Kinetic Blast
R-100
With the damage boost chip-110 (so a 10% boost)
S-150 (+50%)
N-125 (+25%)
CF-125 (+25%)
G-200 (+100%)
G+S-300 (+200%)
G+N+S+CF+damage boost chip-516 (+416%)

Phantom
Psyshock
R-90
S-135 (+50%)
CF+S-169 (+87.5%)
G-135

Superthermal
R-125
N+S-235 (+87.5%)
CF+N+S-293 (+134%)
Glue again didn't increase damage.

Highlights:

-Combat Focus DOES stack with Psi powers but does NOT stack with the Q Beam.
-Glue damage bonus is pretty well exclusive to pistols, the wrench and Kinetic Blast.
-EMP grenades don't stack with Nullwave against Voltaic Phantom.
-Other than these, everything stacks with pretty well everything else with the same rates multiplicatively with the exception of the Shotgun, which gets less of a boost out of everything but Combat Focus (which stacks multiplicatively with it).
-Psyshock and the electroshock mage power are indeed identical to a Nullwave/stun gun shot.
-Psyshock is pretty great. Fast cast, disables s*** and barring Glue is almost as strong as Kinetic Blast for near half the cost. Also kills Cystoid nests without popping them.
-Q Beam lagged behind CF+N+Shotgun/Golden Goose for Nightmare killing. Nightmare difficulty is described as lowering weapon damage by 20%, so I wonder if it'll be affected by this. It certainly has its uses (still kills pretty quick when not using CF to give other sources a boost, stunlocks some things, Poltergeists don't get their explosions when shot by it).
-Rotating through CF, Psyshock, Kinetic Blast and Superthermal isn't enough to kill a Nightmare, but it's pretty close. Kinetic Blast oneshots normal Phantoms and does 230 against stunned military operators. Glue->KB kills a Poltergeist (haven't tried without glue), shock->KB with the damage boost chip kills a Weaver. This is all on Normal though.
-With CF three maxed stun gun shots kill a Technomancer. See little reason to use any other method.