Some suggestions

Hello,

1. Nightmare:
   Having it cause fear is a good new, and an obvious capability given the name. Would it be possible to make it even more nightmarish, floating above ground without leaving foot step (still emitting a trot), ignoring ramps and lower obstacles, without being targeted by anti-air fliers? Perhaps, this "floating" ability could be researched and granted alongside the vanilla Nightmare speed upgrade?
   
2. War Dog:
   Please, reduce their sprite a little, make them Small (well, as small as Dwarves are), cut down costs, BT, and HP, turning them into spammable little pests that don't leave neither bones nor soul behind. They could even be instant produced for a greater cost, just because pups take less time to grow and train than children. This way, War Dogs would act like a "swarm" of cheaper units ahead of any Tribesmen squad. They would be massively used against the Daemons and the Undead to not strengthen them when they die. Of course, they couldn't enter tower and increase their combat and rate of fire.
   
3. Warlords:
   They are heavily armoured, yet riding at the same speed than Riders. Either make them as Scythian Cataphracts, slow and deadly, or make them slashing Riders (not my preference, though). Also, what about making them the Barbarians' generals in place of the Reavers? Reavers would be produced at keep level 4 and could thus upgrade the towers earlier.
   
4. Dark Riders/Slayer Knights:
   I can't help but suggest that they are not only baneful to heroes, but to generals as well, and possibly to Titans. This way, they would keep being useful (as compared to the Queen Spider), when all the enemy heroes are dead or hidden in their towers.
   
5. Regeneration:
   Trolls do benefit from faster regeneration, aren't they? (the same with Hydras)
   Mechanicals could regenerate more slowly, and be healed through Engineer's spell.
   
6. Riding skill (and Knight researches?):
   Are Pegasus considered as Cavalry for this purpose? After all, they are, from a Barbarian stand point (through their cavalry research). Griffons already benefits from XP items and skills, and Wyverns are considered as dragons.
   
7. The Wood Elves: (a renewed rant!) (sorry if I mix TPC with v1.03.25 vanilla)
   In the WBC franchise, I'm not sure that Dryads are considered as Elf-driven Fey. They are full-blood female, "witches" Wood Elves. Imho, they have nothing to do with the Fey (except if they are visiting them). On the other hand, besides Phoenixes, several natural being and/or Fey choose to ally with either the High Elves (Unicorns), the Wood Elves (Treants, Pixies, Sprites), or Barbarians (Lightning Hawks). Let's add the Oakman to the list, without considering however, that they are just dwarf Treants. If Treants had chosen to ally the Fey, the Fey would have produced them.
   This said, it's quite weird that Wood Elves are able to summon local Fey earlier than the Fey Court do (keep-level wise). I'd delay their production to the latest tiers.
   

Rodmar18 wrote:

Nightmare:
Having it cause fear is a good new, and an obvious capability given the name. Would it be possible to make it even more nightmarish, floating above ground without leaving foot step (still emitting a trot), ignoring ramps and lower obstacles, without being targeted by anti-air fliers? Perhaps, this "floating" ability could be researched and granted alongside the vanilla Nightmare speed upgrade?

Not without directly giving it the Floating movement type, which would mean the Nightmare can attack flying and can be attacked by flying.

Rodmar18 wrote:

War Dog:
Please, reduce their sprite a little, make them Small (well, as small as Dwarves are), cut down costs, BT, and HP, turning them into spammable little pests that don't leave neither bones nor soul behind. They could even be instant produced for a greater cost, just because pups take less time to grow and train than children. This way, War Dogs would act like a "swarm" of cheaper units ahead of any Tribesmen squad. They would be massively used against the Daemons and the Undead to not strengthen them when they die. Of course, they couldn't enter tower and increase their combat and rate of fire.

Relax, this is planned.

Rodmar18 wrote:

Warlords:
They are heavily armoured, yet riding at the same speed than Riders. Either make them as Scythian Cataphracts, slow and deadly, or make them slashing Riders (not my preference, though). Also, what about making them the Barbarians' generals in place of the Reavers? Reavers would be produced at keep level 4 and could thus upgrade the towers earlier.

They aren't heavily armoured in TPC. We also already have a new general unit for the Barbarians (in 0.8..

Rodmar18 wrote:

Dark Riders/Slayer Knights:
I can't help but suggest that they are not only baneful to heroes, but to generals as well, and possibly to Titans. This way, they would keep being useful (as compared to the Queen Spider), when all the enemy heroes are dead or hidden in their towers.

They no longer deal bonus damage to heroes anymore.

Rodmar18 wrote:

Regeneration:
Trolls do benefit from faster regeneration, aren't they? (the same with Hydras)
Mechanicals could regenerate more slowly, and be healed through Engineer's spell.

Yes, they get double the regeneration rate. Agreed with mechanical units too. Maybe mechanicals shouldn't regen at all?

Rodmar18 wrote:

Riding skill (and Knight researches?):
Are Pegasus considered as Cavalry for this purpose? After all, they are, from a Barbarian stand point (through their cavalry research). Griffons already benefits from XP items and skills, and Wyverns are considered as dragons.

I wouldn't apply the bonus to fliers for balancing reasons. Fliers have been a terror in 0.8.7 multiplayer so we need to keep them under control.

Rodmar18 wrote:

The Wood Elves: (a renewed rant!) (sorry if I mix TPC with v1.03.25 vanilla)
In the WBC franchise, I'm not sure that Dryads are considered as Elf-driven Fey. They are full-blood female, "witches" Wood Elves. Imho, they have nothing to do with the Fey (except if they are visiting them). On the other hand, besides Phoenixes, several natural being and/or Fey choose to ally with either the High Elves (Unicorns), the Wood Elves (Treants, Pixies, Sprites), or Barbarians (Lightning Hawks). Let's add the Oakman to the list, without considering however, that they are just dwarf Treants. If Treants had chosen to ally the Fey, the Fey would have produced them.
This said, it's quite weird that Wood Elves are able to summon local Fey earlier than the Fey Court do (keep-level wise). I'd delay their production to the latest tiers.

It is a little mixed - High Elves get Celestial Hatchlings instead of Unicorns and Wood Elves no longer get Pixies or Sprites - but otherwise is largely relevant. I agree that Oakmen really are more of a Wood Elven unit rather than Fey. There are some undeveloped plans to introduce a new Gnome unit as the Fey builder so the Oakman can properly become a Wood Elven unit.