Doxy's thoughts on Influential and Hex Maniac
Thematically (in a mechanical sense), Hex Maniac and Influential are both very similar. They are both classes about taking control. Hex Maniac and Influential both seek to manipulate the flow of battle to their favour without doing damage; one does so through mind control and debuffs, while the other does so through status conditions and CS lowering

However, does that by itself mean they should be merged? I don't think so, but this is a bit of a complicated issue. At first glance, we have some reasons to both keep them separate, and merge them.
The reason I see to keep the classes separate is that their fluff is very disparate. Hex Maniac seems linked to witchcraft; curses, voodoo, the like. It's tied to ghosts and their inscrutable forces. Influential is of course linked to Mind Control, which is a strong and prominent pop-fantasy archetype for psychics, and for that reason alone deserves consideration as its own class

The reason to merge them is that on the other hand,  I think the two concepts can be made to go hand-in-hand very well mechanically, to provide a class that has both straight-forward debuffs and more nuanced control options, to always keep your opponents off-balance without being a "nuker" class like the other PSY CLASSES.
So we have to go a little deeper.  Influential as it stands right now, is a class with mostly subpar abilities that are mechanically very similar to what you might expect from a Hex Maniac. Attitude Adjustment is a nice touch, but it's also littered with things like Fear, Imposed Caution, Imposed Focus, Memory Lapse, and Dream Eater - which could ALL fit within Hex Maniac mechanically without too much trouble on the fluff wise (even Memory Lapse is really just disable, after all).

So let's examine why I think Influential is so badly designed at the moment. Mind Control may be a well-known pop-culture archetype, but in my opinion it just isn't a very good archetype to have in an RPG game.
Yes, I'm going back before on saying it's not COMMON, because as Anise poined out, there's spells like Dominate, Suggestion, Charm X, Command, ect. ect. But very rarely are entire classes based on this concept, because it has a strong potential to create IC drama and anti-fun for the manipulated players.

Other systems may be able to squeezy with things like this before there's more infrastructure for dealing with things like this. There's things like immunity to mind-affecting effects, spell resistance - there's a lot of things you can potentially have in place to alleviate direct control over your character.

Does that mean there's no room at all for Mind Control in PTA? I don't necessarily think so. However, the features would need to be worded carefully. And I ideas on how mind control may be implemented, but I'm getting a little bit off track.

I'll summarize in saying that I do not think a class based solely on the idea of Mind Control is a good idea. I do not believe it's worth implementing due to the high potential for abuse of mind control abilities. Morever, since 8+ features dealing with direct mind control would probably be unneccessary and in fact make it difficult to have any cohesive Mind control mechanic, it will naturally tend to create a class that has at most 3 or 4 features dealing with the mind control itself, while other features are mild debuffs that are not thematically or mechanically much different than what Hex Maniac would offer.

So in this aspect, it's my opinion that we would benefit from either merging the two classes, giving Hex Maniac some more nuanced control options besides straight-forward Status Effects ... or that we should keep Hex Maniac as it is (since it's a solid if boring class), and drop Influential entirely.