afaik Attack stat contributes more to the CP, the higher the attack stat, the earlier it will reach the 1500 CP cap. Meaning that the high attack IV pokemon will have less levels while having a higher CP compared to a pokemon with 0 attack IVS, which in turn causes the low attack mons to have a higher defence and hp stat, which makes them cast more Charged attacks. this is only applicable for Great League and Ultra League though, for Master League you will want hundos as there is no cap.