Thoughts?
LeBlanc's medium ~700 range already puts her at solid risk for assaulting targets, as most champions have something pretty nasty they can lob ~700 range. Several melee champions can actually throw themselves that far.
Also - LeBlanc's team-fight damage is pretty much hard-capped at 20% of the enemy team's collective HP. Her cooldowns are kind of low, but not low enough to really be ready when she needs them again, and her reliance on damage just so she can take out 20% removes a lot of CDR options.
Most mages can nuke 50% of an enemy team's HP, all marksman can reach that with auto-attacks alone, most assassins have enough in the way of re-sets, auto-attack power, and mild AoE to hit a 50% mark.
And then dedicated tanks and supports can often cause the equivalent power of a 50% HP loss by incapacitating almost an entire team by themselves, along with the important strategic functions of initiation a fight and locking down priority targets or counter-initiating and peeling priority allies.
If you hit LeBlanc's early power hard enough where it's ~meh power, there's no reason to pick LeBlanc at all, she's one of the weakest damage-dealers late game due to her strategic weaknesses.