An Idea for Swain Changes

I´ve seen Rumors about Swain Changes. His Soul Fragment System should be Changed to a Stack System like Dark Harvest. So you dont Store or Save the Souls, you just Gather them. But i saw, that only the Damage get´s increased for his Demonflare Cast. Wouldnt it be way more Interesting to give him an Increase for the Duration of his Ultimate. For example giving him 1 Second of Duration for every 5 Soul Fragments. Maybe even nerfing his Base Duration from 12 to 10 Seconds would be a good Idea. So Swain would get the long Draining Tank he was Pre Rework, but on a way more Skilled and Rewarding Way then before. I want to hear some thoughts about that Idea.