Here's a thought: What if we had an ADC with a Halo-like shield?

Before you say "Malphite", there's no reason two Champions can't have similar passives. After all, Malphite and Taric both get passive bonus armor.

Now, most ADCs are not known for defense, but Riot doesn't want to homogenize them (if the pre-season changes are any indication). As such, having an ADC with a passive self-shield would be unique, making said ADC resistant (but not immune) to harassment and able to perform tricks such as disengaging from a fight briefly, regaining shields, and then re-engaging the enemy with a "health advantage". If that results in worries about "This Champion has too much HP for an ADC", then lower that Champion's actual max HP and make it more dependent on good shield use.

Sorry if this is out of the blue. I was doing some Halo: Combat Evolved Anniversary this Christmas afternoon. ;)