What if the rangefinder could do this on a spotted ship? 
Because it reveals quite enough details to the ship and having a rangefinder allready diminishes the effect of getting spots.
So an active rangefinder pointing on an enemy ship revealing this type of spot on an allready spotted target imo would be a good reason to start using range finders.
Would this work to mark spotted ships that are partially covered by clouds and would be unspottable had they not been pre-spotted? Otherwise I mean, you can already just see the ship.
"Why do you look at the wall with your rangefinder?"
"I am using the rangefinder to reveal more details of the enemy ship, spotted by our ally, which we can't see, because there is a wall in the way."
"But our ally can see it clearly and we can't shoot it anyway."
"...You can't stop me!"
I think it would look nice when there are too many flares going around. I don't know about you, but I often can't even see my own projectile and hitbox in these flared clouds.
