Are there any new classes yet?

[MaAaT]

I don't think we'll ever see any other classes, because we don't really need team play in most maps. There is no need for tank healer dps strategy, when we can easily kill every enemy. If we ever got a healer class that would be even more hated than tanks back in the day due to low dmg making it effectively useless.
I feel like mage can already be played in very different ways, that work similar to your described ideas. Mage can use fire ice and clock and focus on dot, which would sacrifice boss dmg however or (and this will work even better after revamp) a support playstyle with curse and heal.