Are these low-level passive abilities balanced against each other?

Question

Context

I am working on a homebrew corruption system for my upcoming Diablo themed campaign. You can read more about the system in this chat thread. The complete system is too large and complex for the scope of this question so I will just summarise the relevant parts.

Corruption is gathered throughout the campaign by exposure to corrupting influences. The PCs have the option to either Resist or Embrace the influence when they encounter it. For each of these option there are three sub-options based on how they choose to resist or embrace.

These sub-options effectively form a skill tree that players can advance through as they gain influence. Each branch has 3 tiers of abilities. As the campaign is expected to run from level 1 to level 5. Players should be progressing in this skill tree approximately once per level. I.e. tier 1 abilities at 2nd level, tier 2 at 3rd level and tier 3 abilities at 4th level.

Question

Below are listing the tier 1 abilities for each branch of the skill tree. The intent is for these to be balanced both individually and against each other. No option should be clearly better or clearly worse than the others.

Tier 1 resist abilities:

• Delusion: You begin to dismiss things as illusions. You have advantage on saving throws against being frightened, but you gain vulnerability to psychic damage.

• Defiance: You have found the inner strength to defy even the strongest foe. You have advantage on Strength saving throws, but have disadvantage on Charisma saving throws.

• Radicalism: Others have begun to notice your Radicalism. You have advantage on Persuasion and Performance checks, but cannot be seen to back down from a fight. Your speed is halved when retreating from an enemy.

Tier Embrace abilities:

• Temptation: Giving in has become so easy that it is almost second nature to you. You have disadvantage on Wisdom saving throws, but gain resistance to fire damage.

• Darkness: Your blackened soul has begun to show. You have disadvantage on Persuasion and Performance checks. However, you also gain resistance to necrotic damage.

• Hatred: Your sulking narcissist behaviour has clouded your judgement. You have disadvantage on Perception and Insight checks. However, you have advantage on saving throws against being charmed.

Players can only gain each ability once. However they will stack with the other tier 1 abilities. For example, if a character takes both Radicalism and Darkness abilities, the Advantage, and Disadvantage on Persuasion and Performance checks cancel out, leaving them with the speed deficit when retreating, and the resistance to necrotic damage.

I would like to know a couple of things:

1. Are these abilities balanced individually? I.e. Their bonus and penalty are roughly equivalent and giving them to a PC will not unbalance the game.

2. Are the abilities balanced against one another? I.e No ability is clearly better or worse than the others.

Answer 1

If the PCs pick, the bonuses are better

These assessments are all based on my experience playing official content. If your campaign takes place in the Plane of Fire, is mostly political intrigue, or faces mind flayers more often than cultists, then that will affect balance.

Resist

Face characters will take Radicalism, everyone else will take Delusion, and no one will take Defiance.

• Delusion. Psychic damage is rare, but vulnerability is dangerous. In my experience, you're more likely to face the frightened condition (ghosts, the fear spell, dragons) than psychic damage (mind flayers). The bonus is a bit better than the deficit.
• Defiance. Strength saving throws tend to be save-or-stand-still, while Charisma saving throws tend to be save-or-don't-play-the-game. Neither of them come up that often, so I'll defer to the worse effect as the more important save. The bonus is worse than the deficit.
• Radicalism. I have only seen a handful of successful retreats in 5e; the system just isn't designed for them. Advantage on Persuasion and Performance is invaluable for a face character. The bonus is significantly better than the deficit.

Embrace

Face characters don't really want to take any of these, Wisdom characters will take Darkness, most others will flip between Darkness and Hatred, and the risk-takers will take Temptation.

• Temptation. Wisdom saving throws tend to be save-or-don't-play-the-game, which players tend not to like. That said, fire damage is one of the most common damage types. A character that's already going to fail most Wisdom saves could take this if they're willing to risk it. The bonus is about the same as the deficit.
• Darkness. Barbarian not care if no talk good. Barbarian want lich fingertouch no hurt so bad. Only a non-face character will take this, so I'd say that the bonus is much better than the deficit.
• Hatred. Perception is one of the most commonly used skills. Insight is up there as well. You've got your party to take care of that for you, though, right? Charm is a common save-or-don't-play-the-game condition, so the bonus is better than the deficit.

Conclusion

If the PCs get the chance to pick, they can min-max the bonuses and deficits pretty easily. Characters are generally rewarded for specializing and these bonuses allow them to do so. Being significantly worse at something you're already bad at isn't a big deal.

How often are you relying on the 10 WIS warlock to pass a DC 15 Perception check? They're already going to fail 70% of the time. Why not make it 91% in exchange for raising their chance to resist charm from 45% to 70% (for a DC 15 save)?

When compared to other options in the same group, the Embrace ones are more well-balanced. The Resist options are almost entirely decided by if your highest stat is Charisma.

Lastly, inter-character balance is dominated by Radicalism. A face is likely to use Persuasion every session (sometimes multiple times per session), while charmed, frightened, fire, and necrotic come up less often. That probably won't break the game, but an ability that is used more often will be perceived as more powerful than one that is rare.