Exhaust range is 650- that should allow you to drop it on anyone who is in range to auto you excepting ultra ranged champs like Senna. And yet it isn't, as anyone who's ever been rooted by a Morgana knows. You start getting hit by the opposing ADC and you can't Exhaust them because somehow they outrange it. Maybe Exhaust is center targeted and autos are edge targeted?
Its probably something to do with exhausts ability hitbox, if its centre to centre or edge to edge like auto attacks.
Best example I can think of is nasus e and zilean e: Nasus e range is 600 and zileans e is 550 yet anytime in aram where I click zilean with my e he can apply his slow without me being able to slow him.
Honestly who knows how half the things in this game are coded but I think you might be right about exhaust being centre to centre, I think the only summoner spell that isn't is smite, maybe also ignite but not sure on that it just seems more reliable.
There's alot ot issues with range in game. Varus with 575 range can be auto'd by every 550 range adc even when they are rooted by his ultimate and you are standing at max range.
Take Barrier instead of Exhaust. Now range isn't a factor.
