Are auto attacks the source of most balance problems when upfront power is tied to them?
To me it seems that whenever you attach a lot of power to AA's, an objectively binary mechanic, you always have significant balance problems around them for the simple fact that once you're in range it is guaranteed to work. AA's have the same problem as point and click abilities with upfront power and Riot is slowly phasing it out because it really limits kit power and offers no counterplay. Don't forget empower'd AA's are also in this basket too.
How can you add power to W without it going out of control, why isn't it just added to or triggered by abilities instead of AA's?
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Q packs a punch and feeds his passive, why not have each consecutive hit empower his E, then give it a delay and deadzone like Darius' Q
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This guys kit is so binary and behind you even gave his E a built in 
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Just bonus damage on the 3rd hit. Really? It's not like there are tons of items that exacerbate and magnify this. Give any champion who has passive empowerment the condition that it empowers skill shots and not AA's, give them a skill shot if they don't have one, it doesn't need to be fancy. So what by late game they AA so fast it's on every skill shot, they still have to land those skill shots.
Imagine if Darius' Q was instant and couldn't miss. That's what empowered AA's are, how can you put anything interesting or powerful on to something like that without it eventually breaking the champion one way or another. There was even a time when Darius Q was instant, remember that shit? Remeber how daft that was?
Point and click is okay when there are additional conditions to reach its full potential like Poppy's E must collide with terrain, otherwise it must remain simple and impotent like Darius' W, or it will hold the rest of champ's kit hostage like Warwick's ult.
I wouldn't do away with AA's I think they definitely have their uses but shouldn't be the main application of mechanics and damage. Maybe this could fix a lot of on going problems, maybe not. Just an observation.