How can crit ADCs get a better early at the cost of their late?

{quoted}

I feel like we need more crit based items. if we are able to separate Lethality items from ADC's to the point where they aren't building solely that, then we will need more crit items.

RIght now, there are only and for Crit and Damage, and , , , for Crit and AS. Hurricane isn't even viable on a good amount of ADC's and neither is Rapid Fire Cannon.

I think we need more Crit items in general, making 100% viable again and balancing out ADC's that get too much from Crit. We need to separate Lethality for ADC's while still allowing for Armor Pen-based ADC's like Jhin to still have power and not have to build Crit to do well. It might be a balancing nightmare, but it needs to happen.

I don't actually think that helps with OP's Question. That would make their late game more powerful, but without really enhancing their Early game. However, I might consider buffing the items we already got.

If you want to give ADC's more early game power, they need earlier item spikes. But right now, Most AA centeric ADCs require at least two items, IE/ER and then one other crit item. (usually Runnans) In the past, their was a point where IE was that one item spike thanks to a large 75-80 AD and 25% crit chance. (Back in an era where people cried about Crit being broken)

But to answer OP's question more thoroughly, it's rather unlikely for a crit ADC to have a stronger early game spike, without overpowering his late game. And That's simply due to the scaling nature of Crit. Other caster Oriented ADC's will have a much more limited scaling if they rely on AD and Lethality, and some like EZ rely maily on the spell blade passive on Triforce. But Crit scales well with both AD and AS.

{quoted}

early game is fine but they hit a mid-game slump because IE alone or a zeal item alone doesn't add much damage without the other, so the adc's best choice is the frankenstein mess of the biggest raw AD basic item they can afford on their first back and then a zeal item, leaving no room for sustain, defense, or utility until way late into the game.

+ / / is pretty standard, though.