Really hope the lower the AD scaling of his Q passive and/or lower the scaling from the souls. Lulu's passive only gives 87 extra magic damage at Lv. 18 and is already considered good because it's a half stacked BT's worth of damage. The passive on Thresh's Q can easily get to 100 damage minimum by level 18 and continues to scale ever higher as the game goes on.
The other alternative is to make souls drop less frequently from standard creeps, meaning that it will take longer to get that 100 on hit damage. --- Generation 30: The first time you see this, copy it into your own signature (on any forum) and add one to the generation number. Social experiment.