House-ruling spells about evil and good to give them back their flavor from old editions

Question

As an ex D&D 3.5 and D&D 2 player, I feel bad that 5e don't make spells that about evil and good (like "Protection from Evil and Good" and "Detect Evil and Good") don't actually interact with alignment. For me it was all the flavor of those spells in older editions was the fact that they affect alignment.

Here is the stat block for the spell I'll use as an example:

Protection from Evil and Good

1st-level abjuration

Casting Time: 1 action
Range: Touch
Components: V, S, M (holy water or powdered silver and iron, which the spell consumes)
Duration: Concentration, up to 10 minutes

Until the spell ends, one willing creature you touch is protected against certain types of creatures: aberrations, celestials, elementals, fey, fiends, and undead.

The protection grants several benefits. Creatures of those types have disadvantage on attack rolls against the target. The target also can't be charmed, frightened, or possessed by them. If the target is already charmed, frightened, or possessed by such a creature, the target has advantage on any new saving throw against the relevant effect.

Detect Evil and Good

1st-level divination

Casting Time: 1 action
Range: Self (30 ft around you)
Components: V, S
Duration: Concentration, up to 10 minutes

For the duration, you know if there is an aberration, celestial, elemental, fey, fiend, or undead within 30 feet of you, as well as where the creature is located. Similarly, you know if there is a place or object within 30 feet of you that has been magically consecrated or desecrated.

The spell can penetrate most barriers, but it is blocked by 1 foot of stone, 1 inch of common metal, a thin sheet of lead, or 3 feet of wood or dirt.

I think about two possible house-rules to give them back their flavor:

• Soft modifications: "Protection from Evil and Good" stay the same (because I didn't found a balanced version for the spell), but "Detect Evil and Good" give the alignment of all creatures that are in the area of effect plus all other information the spell already give
• Hard modifications: Go back to the old version of the spells
  • "Protection from Evil and Good" you choose an alignment (except neutral) and all creature of this alignment are affected like the spell actually does for some creature, but don't target them for what they are
  • "Detect Evil and Good" tell you what is the alignment of all creatures in affected area, but not there nature.

Since I DMing in Eberron (a world were bad guys are not always evil aligned, good guys are not always good, and creature don't follow their "natural" alignment), I think that both houserules are balanced in some way, but I don't know which would be the most balanced, or if those house-ruled spell are balanced enough.

So here I am to ask for help: which one seems to be the most balanced?

For the record, I playtested the soft version, and it end up just adding more roleplay option for the players (e.g. defend themself by explaining that being evil aligned don't always mean that you will stab the paladin in the back if you can). I didn't already tested the hard version because it's a big change in what the spell does, so I preferred to ask if it could be unbalanced in some way before, and find a fix if it is, and then playtest it.

Answer 1

Both approaches are more powerful than the standard spells.

All of these modifications to the base spells are more powerful and versatile than the base spells, because they add additional features and abilities.

Soft modification

Detect evil and good normally lets you sense the location of six of the fourteen types of creatures, including invisible, hidden, and disguised creatures.

This modification would extend the spell to cover the other eight monster types, including very common categories like humanoid and beast. In Eberron, where extraplanar creatures are rare, and city adventures are more common, this version of the spell would be considerably more useful.

Giving the full alignment of creatures also makes the spell more useful. For example, you can tell a changeling impostor apart from the real person if their alignment doesn't match. You can tell a shapechanged druid apart from an animal because the druid will have an alignment.

Hard modification

Detect evil and good as described is functionally the same as in soft modification.

Protection from evil and good, in combination with detect evil and good or foreknowledge of typical monster stats, opens up that spell to protect against every creature of every type. If it works like the 3.5 version, it affects all creatures of one alignment axis (e.g. "evil"), making it broadly effective.

The modified spell has three main drawbacks:

• It no longer functions against neutral creatures. However, most of the creatures the standard spell works against are non-neutral, with only twelve such creatures in the Monster Manual having True Neutral alignment, mostly elementals.
• It only protects against one alignment at a time, meaning that it's of limited use against groups of mixed alignment. However, teams of opposite alignment rarely work together.
• Since alignments can change arbitrarily in Eberron, this spell can be really unpredictable, which frustrates players. They might cast it to protect against evil when fighting a demon who turns out to be non-evil. It's too easy for this spell to have no effect without any way for the players to know this in advance, unless they pair it with detect evil and good, at which point it becomes trivial.