Many of the subclasses recently previewed just feel to me like old concepts from other classes re-applied to a new class. Twilight is basically a shadow option for clerics, Aberrant Mind a Sorcerer version of the GOO Warlock, Wildfire a (fire) elemental option for druids... I don't like this kind of crossover because I like classes to be separated, I don't like the idea of having the same theme across many classes. And it's starting to feel like half of these designes are generated by looking at gaps across classes.
I also see way too many abilities that really aren't nothing new, just repackaging of the same. Twilight Druid has... darkvision, temporary hit points, bonus spells (but none is a new spell). Minimal novelty e.g. in the darkvision range but meh. I can design subclasses like that by myself, without having to buy a book.
What is new is otherwise goofy or too narrow in concept, and apparently new mechanics too focused on minutias and fiddly bits . The Onomancer is indeed a novelty concept, but still doesn't impress me when at the end you are still just boosting damage, healing yourself or imposing disadvantage on saving throws...