Everything about Diablo 4’s damage system is about stacking as much Vulnerability damage, which really ends up removing player choices. I have a better idea. Most of us know that Vulnerability have it’s own multiplier, what if the highest of vulnerability damage, damage vs slow, damage vs close, damage vs far, damage versus frozen, chilled, stunned etc… will be used as a multiplier. For an example if, I you have 120% vulnerability damage, but you have 170% damage vs close targets, then 120% vulnerability damage ends up in the bucket with the other additive multipliers, and now damage vs close targets becomes the multiplier as vulnerability damage is now. In this way, people have more freedom to their builds.
Sorry man, but this wouldn’t work. Vulnerability requires another intentional event to happen for it to be applied and it’s much more difficult to obtain +vulnerable damage. If they did what you mentioned, EVERYONE would simply drop vulnerability completely - it would have zero usefulness.
Not saying the other part wouldn’t be an interesting twist - I think you’re onto something that could be fun, but it would be a major change and would create major balancing issues (as Blizzard would have to make sure each and everyone of these potential buckets isn’t overpowered, leading to players dumping most/all of the other options).