I honestly believe Storming to only be an issue in Sanguine Depths, the place is a long hallway with the only open room being the 3rd boss room, beyond that I do not think Storming is that bad, not as a Melee, nor as a Tank, I think Necrotic causes far more issues and if it is a Tyrannical week, it is just too damn much, if anything should be done, Tyrannical should be nerfed or removed, there are some weeks I just don't bother with Mythic+ because Tyrannical is the bigger issue than Spiteful, Necrotic, Storming, or any of those combined, just replace Tyrannical & Fortified with new affixes.
Some affixes should be more "intelligent":STORMING should have it's size according to the type of player is near at spawning moment: be smaller if spawned in melee range and bigger for ranged players. Slower in melee. Slower if there is another storming near. Faster for ranged.SPITEFUL, VOLCANIC and EXPLOSIVE should have a similar intelligent/adaptive behavior in terms of density, respawn time, and range.SANGUINE should be smaller in corridors and tight areas, bigger in open and wide areas. Despawn quicker in tight areas, and last longer in open areas.NECROTIC should apply less often when too many mobs are aggoed, more often when just one or two mobs are aggroed. Not in a linear way, so it still penalize aggroing too many mobs, but less then the linear way it does today.