yep i think you figured it out, sounds good to me.

but i still like the idea of kind of blinding the enemy with "steam" for a short time

it should have some offensive capability

Every critical hit gives like a .5 second blindness?

maybe something like an airblast so soldiers can reflect stuff too?

Cool, but just to add...

Charge Shot would be a Mini Crit and also disables buildings for 5 sec.
-15% Movement Speed

hold for charge: to lang holded will explode and cast jarate like effect on you
if hit enemy the same happens, when equipped, 20% blast resistance but marked for death

Rocket jumping weapon?

If valve wanted that, they would just update the rocket jumper.

Steve rocket jumper is just ment for practising with no damage

Ithink the stats are alright but i was thinking that a where you fire a mini sort of exspolion stays there for about 3 seconds or something like that

i think dis is good:
+ -15% dam. to self
+ right click: use 3 rockets for a rocket that does no dam.
but does x3 push power.
- -50% dam. to buildings
- +15% fire vuln.

a steam launcher might work like this:
-75% ammo in clip
+25% reload speed
pressurized launcher: hold down the attack button to add pressure to the launcher.

the lower the pressure the higher the blast radius is, but the rocket will not travel far or fast. if the pressure setting isnt in the yellow (like a demomans sheild) the damage is reduced by 10%

the higher the pressure setting the farther and faster the rocket goes, but loses blast radius percentage. once pressure setting is in the red the rocket gains a 10% damage boost and gains a push force but blast radius is extremely reduced (almost like the direct hit)

if rocket is held for too long (once the meter is full) the rocket will launch as though it were launched by a stock rocket launcher.

+ +25% clip size
+ -30% damage to self
- -20% damage penalty
+ when crits blinds for 0.5 sec

Pros:
+40% explosion radius
+20% knockback
Cons:
-rockets are affected by gravity
-no random crits

But wouldn't dat Stat make easier for you to die?