I shall add to your list:
-10% Fire Vunerability

it does damage based on the distance i which the projectile travells
30-100 damage on bodyshot
100-250 damage on headshot
-30% bullet ressistance

They are interesting but my suggestion:
Lightweight Gun
The new, 20% more cool weapon from the Queen of England

+ When Headshot: 5 seconds of health regeneration (2hp/sek)
+ 10% faster reloading
+ If you're killed Backstab, Spy will be marked for death
- You're about 20% slower

+20% run speed
+10% reloading
+10% bigger scope
-25% ammo capacity
125% time to pull back

I say all the stats that GrandpaPancakess said,

PLUS:

When you hit mouse 3 while scoped, you will activate the next stage of zoom.
First click: x1.5 zoom
Second click: x2.0 zoom

Mah stats:
-On no-scoped headshot crit
-Damage increases or decreases depending on the distance between the shooter and the victim
-The gun doesn´t charge shots
-Weapon draws 30% slower
-Weapon shoots projectiles NOT bullets
-Projectile speed is max charged huntsman arrow by 2
-35% less damage from bodyshots(scoped or not)
-Accuracy decreases while running,moving or if pushed from enemy attacks
-20% slower firing speed

+15% movespeed while scoped
+no flinching while scoped
+ you can jump while scoped
-jumping while scoped drains 20% of your charge
-10/20% damage penalty while unscoped
-20% damage on scoped bodyshot

Here is my Idea for some stats,

+Deals more damage the farther the bullet travels ( base damage of 25 at no charge)
-5% slower projectile speed ( to make it travel faster than a normal bullet, but not hitscan)
25% more bullet damage taken while scoped.

Thoughts?

I'm thinking, how about a reversed sniper rifle? One in which the sniper's charge start at 100%, but then drains the longer you stay scoped in, making a person rely more on quickly scoping and taking a shot. Ofcourse to balance this out it would have to deal less damage on full charge, charge meter drops much quicker than a normal sniper rifle fills and/or will take longer to scope in/out.

cool

High damage, high charge rate, lots of resistance to lots of things, SLOW FIRING RATE?

A weapon for a hasty hitman!

Upsides:

Starts at full charge when zooming in
+10% firing speed

Downsides:

Charge goes down instead of up
+20% fire damage taken
20% slower walking speed when zoomed in

(I didn't steal you idea ''the devil hunter'', i had the same idea

Originally posted by Sweddy:

(I didn't steal you idea ''the devil hunter'', i had the same idea

Mmmhmmm... Sure.

um i think
+30% damage
+50 damage with headshots
Custom scope to help aim
User does not use lazer asist
-25% reload speed
While scoped, -10% movement speed