Warmind Cells, but more versatile?
Frankly, as sad as I along with many others were to see them nerfed, Warmind Cells are still fairly strong, especially with the right build (ex. bottom tree Dawnblade w/ Rage of the Warmind and Wrath of Rasputin). But I'd love to use Warmind Cells as a Stormcaller without being forced into using the Seventh Seraph weapons or something like Ticuu's/Sunshot. Nothing against those, I'd just like a bit more freedom.
I think if the other elemental affinities got ways to spawn Warmind cells, that'd make them a viable way to compete with Elemental Well/CWL builds in PvE. Perhaps mods that allow Arc melee kills to have a chance of spawning a Warmind Cell, or maybe Void super final blows have a chance to spawn them. For Stasis, there could be a mod that allows for a chance to spawn one when shattering a frozen enemy. Then there'd be other mods for Stasis affinity, such as Warmind Cell damage slowing combatants and granting ability energy to your lowest ability on detonation.
Buffing some of the mods would help too, as going out to collect a Warmind cell is not exactly a good game plan for things like Grandmaster Nightfalls. Mods like Modular Lightning and Strength of Rasputin could proc on Cell destruction as well (Side note, Modular Lightning and Reactive Pulse should proc Conduction Tines on Crown of Tempests. No, I'm not biased, stop looking up my stats).
TL;DR Buff Warmind Cell accessibility through new/improved mods