Nerfed Witch - Is this class still playable?

[Psyren]

@Rumo:

There is no save. Intimidate follows a fixed formula to generate the DC (10+HD+WIS mod) and that´s pretty much it.
Fear effects are cumulative. Hit a target more than once and they move to the next worse condition, accumulating mali along the way. So Shaken > Frightened > Panicked > Cowering.

While the latter is true, Intimidate specifically does not stack:

"Using demoralize on the same creature only extends the duration; it does not create a stronger fear condition."

There are ways to use Intimidate to get a target above Shaken however, e.g. the Skill Unlock version, or intimidating to shaken and then using a different fear effect after that.

[Florian]

Not relevant due to the nature of Slayer-only feats that allow stacking.
It´s the strength of the Slayer and Vigilante to be able to do just that.

[Rumo]

Yes, I understand that now. And I see that the cumulative boni from Favoured Terrain are nice and worth more than what a feat usually gives (+2 Initiative is worth half a feat, +8 Skill points in mostly good skills is certainly worth more than the other half. So it's picked on general grounds because it's good, not because it synergizes in any specific way with the Intimidate skillset.
I still wonder how easy it is to win the Intimidate checks at a regular basis. Maybe I should invest more in CHA? Like STR 14+2, DEX 12, CON 14, INT 10, CHA 14? That would be Intimidate 15 at level 10, as opposed to Intimidate 12 if I dump CHA. Quite a difference if pushing them to cowering status is a goal...

[Florian]

Keep two things in mind:
Intimidating Prowess lets you add both, STR and CHA to Intimidate at the same time.
(Shifting points from STR to CHA is a zero-sum game here and STR is the overall better attribute)
Once you hit level 7, the Stalker class feature will add the Studied Target bonus to Intimidate as well. (The Lenses will add 4 virtual levels to that once you acquire them, beefing up that bonus as well)

[Rumo]

True, but my suggestion would shift 1 point of STR towards 4 points of CHA (and 2 INT -> 2 CHA). And it seems to me like you can never have enough Intimidate anyway, with the appearance of higher devils certainly being just a matter of time. And Pit Fiends or Cornugons probably not being easily impressed by puny humans.

I was also thinking of this advice from the campaign manual: Take note that Hell’s Rebels has strong themes of political intrigue and puts the PCs into the roles of being leaders of a rebel group, the Silver Ravens. As a result, Charisma is a more important ability score in this Adventure Path than most [...]

I have to admit I'm still a bit concerned about the action economy. Turn 1: My initiative is rather high thanks to all these favoured terrains. But what am I going to do with it? For Dazzling Display to be worth spending a full-round action it seems to me like I need to hit at least 2 opponents. But from my humble experience, having 2 opponents within 30 (or to be more exact 35) feet at the start of a combat is not happening all the time. So do I wait for them to come? Do I position myself somehow for a turn 2 Dazzling Display? Or a turn 2 Sneak Attack? If the latter, wouldn't it then be better to go for Cornugon Smash and intimidate the guy while killing him? I mean, I'm not always in the middle of a crowd of 10+ weak-willed soldiers who will all panick at the sight of my muscle+sword display.

[Florian]

I was also thinking of this advice from the campaign manual: Take note that Hell’s Rebels has strong themes of political intrigue and puts the PCs into the roles of being leaders of a rebel group, the Silver Ravens. As a result, Charisma is a more important ability score in this Adventure Path than most [...]

Happens, yes. Diplomacy is a thing and a Half-Elf (Skill Focus: Diplomacy) in a high CHA class is practically a must-have. The question rather is whether a combat-focused class can and should actually go really deep into this topic.
Edit: Keep in mind that one of the early bonus feat choices is Persuasive...

I have to admit I'm still a bit concerned about the action economy. Turn 1: My initiative is rather high thanks to all these favoured terrains. But what am I going to do with it? For Dazzling Display to be worth spending a full-round action it seems to me like I need to hit at least 2 opponents. But from my humble experience, having 2 opponents within 30 (or to be more exact 35) feet at the start of a combat is not happening all the time. So do I wait for them to come? Do I position myself somehow for a turn 2 Dazzling Display? Or a turn 2 Sneak Attack? If the latter, wouldn't it then be better to go for Cornugon Smash and intimidate the guy while killing him? I mean, I'm not always in the middle of a crowd of 10+ weak-willed soldiers who will all panick at the sight of my muscle+sword display.

Most combat happens indoors in urban environment with a lot of mooks at hand. If your group is cool with it, do some "training" and engage with 2 room at once to save time and resources.

[Rumo]

Most combat happens indoors in urban environment with a lot of mooks at hand. If your group is cool with it, do some "training" and engage with 2 room at once to save time and resources.

I have to admit that I don't understand this. What kind of training do you mean, and what's 2 room at once?
I suppose I need to talk to our Bard. If he is planning on using many fear effects, going for Disheartening Display might be very strong. Otherwise it seems to me that Dreadful Carnage is worth considering. Kill one guy with a powerful sneak attack, make everyone else freeze in shock.

[Florian]

I have to admit that I don't understand this. What kind of training do you mean, and what's 2 room at once?
I suppose I need to talk to our Bard. If he is planning on using many fear effects, going for Disheartening Display might be very strong. Otherwise it seems to me that Dreadful Carnage is worth considering. Kill one guy with a powerful sneak attack, make everyone else freeze in shock.

"Training" (build a train) is an older term used when you actually want to attract more enemies to an existing encounter, maybe to hit harder with AoE attacks. For example, you have a house with three rooms, all have 4 enemies, it might actually be easier to get them in one single fight and just nuke ´em in one go while the buff durations still hold.