The story with Aether/Chaos is that they were originally intended to be damage wielded by enemies and not by players, but somewhere along the way in an effort to distinguish some classes early on, we ended up adding those damage types to mastery skills.
I think if we went back and did things all over again, we’d have stuck to those damage types being exclusive to enemies. Makes Aetherial and Chthonian powers feel more distinct than just “things players also do”.
Having less damage types is also something I think would be good if we did a sequel. Too many damage types means it is harder to overlap skills between masteries, makes gearing more difficult and muddies resistances.
As for dots being separate from flat damage for % bonuses, that’s a relic from TQ. By the time we had a moment to breathe during development and think about it, it was too ingrained in GD to rip out without significant time invested. That said, most end-game sources of damage that boost a flat damage now also boost the respective dot, so it’s not that big a deal anymore. For clarity’s sake, we would not do that again for a sequel.