Extra damage? so it's quite made for a bodyshot that instakills the Demoman if made like that

Something like other Dr. Grordbort weapons? What about this:

+ Square view when zoomed in, thermic vision
+ Able to penetrate one layer of wall / whatever
+ Does not use ammo
- 80% damage against buildings
- 10% damage
- Fires tracer, energy rounds

But not able to penetrate in spawn walls.

^ very gud idea

Laser weapons were employed in the cold war (Supposedly) to neutralize enemy missiles and vehicles, perhaps this would work well behind focused around being able to hit targets around walls! (Such as sentries and unsuspecting targets)

Possible Stats #1:

lvl (x) microwave gun
+ Beam Reflects Off Of Walls (Once)
- Cannot Be Fired Until Fully Charged
- Fires Tracer Rounds

These stats would allow the player to perform the classic demoman strategy of attacking enemies using a wall, however with less splash damage and with more distance, however it could also endanger the sniper using the weapon.

Possible Stats #2:

lvl (x) pulse ray
+ Uses Scope Charge As Ammo
+ Projectile Gets Faster With More Charge
+ Shooting Does Not Make The Sniper Exit The Scope
- Damage Does Not Increase With Charge
- Fires Projectiles

This setup would allow the reckless sniper to fire low-speed projectiles or a more experienced sniper to reap the advantages of a single high-speed projectile, it would also make the sniper have to rely almost exclusively on headshots to compensate for it's low-damage, I do not prefer these stats as they may lead to spamming tactics.

+destroys projectiles while scoped
+does not use ammo
+30% damage to enemies on fire
+20% damage to enemies who are being healed (weather it be by medics or dispensers)
+full charge hits all enemies connected via a heal beam
+if full charge kills the target, target explodes, dealing damage to nearby enemies
-full charge does not deal extra damage
-shoots tracers
-30% rate of fire
-marked for death while scoped
-30% damage while unscoped

+Alt fire places camera that is able to be viewed by the monitor, is destroyable.
+15 to 25% firing speed
-Placing camera costs ammo
- 25% decreased primary ammo

-Can only be fired when fully charged
+Does not use ammo
-15% damage
+35% charge rate
-Fires Tracer Rounds

+Does not use ammo
+25% charge rate
+On successful full charge shot on target: creates a small explosion that can hurt other enemies besides the target (40-60 damage)
- Can only be fired when fully charged
- Fires tracer rounds
- Knocks user abit back when fired

i think it should give a short affect of burning a bit like the sydney sleeper, and there should be a knock back

+ Can see enemies around walls when scoped. (except cloaked or disguised spies)
+ Does damage to players connected by heal beams when fully charged
+ 15% damage when fully charged
- +15% charge time
- Bright flash and loud noise when fired
- 50% damage to buildings

+75% damage to buildings
+25% damage to players soaked in water
-15% damage to players
-Marked for death for 3 seconds after shooting
-Fires tracer rounds

These stats give the weapon a clear advantage over enemy buildings. This combined with the damage decrease against normal players makes it more of a team-player weapon than a weapon where you just run around and have fun. The 'marked for death for 3 seconds after shooting' stat encourages players not to spam the mouse hoping to get a lucky shot. The extra damage against players soaked in water is simply there because of the idea of this being an electrical weapon.

Constants:
No ammo use
Tracer Rounds
Variables:
+ Full charge, lights target on fire
- Whatever % to Buildings
-No headshots
OR
+Full Charge, small explosion radius around target
+ Whatever % to Buildings

-Cannot actually scope in
-must use zoom of the viewfinder
-30% less time between shots
-15% faster movement speed when equipped
-15% less damage

on kill: turns victim to ice

How about you stop overdoing it, and maybe just do:
20%+ damage vs building
charge rate increases on buildings destroyed
10%- normal charge rate
wait now im overdoing it.