WHM seems to still be getting the (very short) end of the stick here. Most jobs aren't big fans of speed buffs and some outright dislike them because of how they can mess up timings or make it hard to weave. With the game consolidating to only mp I doubt MP economy is going to be a huge focus either, seems like 2 bits of utility that are the least needed or requested. WHM would definitely still be losing out to DiAST here by a huge margin.

The AST buffs, as you said, can literally replace a ninja. Sure, they're less reliable than Trick Attack but with the way they've been letting us mitigate more rng with AST I don't think it would be that hard to line up. This version of AST would just be too overpowered.

SCH is the least problematic of the 3 at first glance but that could be because it's already so OP we don't even notice - the mitigation from Selene in particular could be a huge way to cheese mechanics when combined with other things like Critlo and even Largresse'd Noct shields.

All in all this continues the story of WHM being left behind for raiding and cements the SCH/AST meta except for extreme speedkills which would likely go double AST unless they were LB cheesing something. They're interesting reworks but also wildly unbalanced and seemingly without thought to what the raid community actually desires in a comp.