kany suggestions?

Kayn should just get like a straight ad nerf in darkin form by a low percentage like kalista, so as to punish darkin kayn for going full ad. Ideally sub 10% and i think hed be golden. If he wants to go assassin he should have to go blue. If he goes darkin he should be building much beefier and so a percentage ad nerf wouldnt hurt him building tank and lifesteal. The fact he changes form should mean something from the otherside, Every kayn i fight goes darkin for knockup and lifesteal then builds assassin, ult drops tanks that you cant just outheal and you have enough ad to be the assassin you should have to go blue for, while it does fall off, until late in the game AD Rhaast can assassinate just fine while being so difficult to kill. Maybe the ad debuff on rhaast form could start at its biggest then move down the later in the game so as not to hurt his late game dmg -10% when you first get darkin down to 5% lvl 18