Kailista smite damage E no end in site

To start off with I have nothing against Kailista as a champ goes. I have played her, played beside her and against. As far as a champ she not over powered but as far as objective control goes shes so strong. The passive power from her E (Rend) stacks up two 254 spears. While Champs with similar abilities their stacks only go up to the single digits. For example Twitch's E only goes up to 7 stacks and has a less than 60% ratio. It does reduce the damage taken after the first but even a reduction in damage. So maybe a reduce in damage stacks or reduction in stacks is needed.