I think E6 was a great solution to the wonky power scaling of 3.X, but I’m not so sure the idea ports over well to 5e. But if you wanted to do something similar, I’m not sure 6th level is the right level to stop at. I would at least go to 8th so you’ve hit two ASI levels, but no higher than 10th, since 11th level is the start of the next tier.
As for what to gain on level up… I feel like “demi-levels” are too complex, and also wouldn’t feel like an E6 system. Just a powered-down version of regular level advancement. Instead, I would look at what scaling you want to remove. HP? Proficiency bonus? Class features? Damage per round? ASIs? Then just remove whatever you don’t want to scale from level up, and keep the rest.
@clearstream I like your revised character progression, but I feel like
@Charlaquin is correct here. This isn't really an E6 system. Its an E11 system with powered-down progression after level 6.
Does that matter?
No, not at all. I'd just call it something else; "low power, high fantasy 5e" ... or some such.
[...] I've drafted rules that end scaling at 6th, and then offer "demi-levels". I'd love some criticism. Does the overall structure feel right? Are the four example classes fairly balanced? Any obvious gotchas or omissions? Note that the intent is that demi-levels are much weaker than normal class levels. Although they go up to 6+5, the third attack for Fighters (and all the scaling implied around that!) is cut. Below, the proposed rules,
I don't think you need to call them demi-levels, since you can put your revised scaling into the new rules directly. But the 6+4, 6+5, etc. is a cool notation.
5E E6
Normal character level advancement stops at 6th level. After that, a character who gains the specified experience point total to gain a new level, advances instead by an increment called a demi-level. Their level is then denoted 6+1, 6+2, 6+3 etc. No further full levels can be gained, and scaling terminates. Meaning that,
- The maximum number of hit dice is 6
- The highest proficiency bonus is +3
- Cantrip effects don’t increase past 6th level
- Class and subclass features granted by full class levels, like Extra Attack, Sneak Attack, Spellcasting or Wild Shape, don't scale further
There are some features that need class level scaling to be worthwhile, like monk ki points. Being stuck with only 6 of those would make 6+5 monks feel pretty stunted. Similarly, you'd want to think about exceptions for subclass features that scale with level or proficiency bonus. Getting stuck with 6d8 psionic power dice as a psi-warrior would also feel pretty lame--their dice would only ever scale once, at 5th level. Unlike the reduced scaling of sneak attack, extra attack, or spells, I think these kinds of features would feel almost vestigial. You'll need to look at them case by case.
Also, I see that you left a lot of the subclass features in the demi-level progression. I generally like that but, and I'm sure you know this, some subclass features have a lot more power in them than others and some classes have a lot more power in their subclasses than others. Rangers and Monks shouldn't get their 11th level subclass features, since those are setup to be (roughly) equivalent to fighters' 3rd attack or paladins' improved divine smite.
And, while you took the 3rd attack away from fighters, I notice that you didn't take the equivalent 11th level power spike, relentless rage, away from barbarians. Any particular reason for that?
In summary, demi-levels are ignored for features that scale with class or character level. That notwithstanding,
- Features that trigger replacements, such as sorcerer spellcasting allowing a character to replace one spell they know at each level, continue to do so at each demi-level
- Class and subclass features granted by demi-levels are gained at their lowest level, and don’t scale further
- Demi-level advancement tables can contain express exceptions to the above
I'm not sure what you mean by "Class and subclass features granted by demi-levels are gained at their lowest level, and don’t scale further", can you give an example?
Hit points after 6th level
No additional hit dice are granted beyond 6th level. Instead, each time you gain a demi-level, roll all your hit dice, adding your Constitution modifier and any bonuses from features like Toughness to each die. If higher, the roll replaces your hit point maximum.
Cool!
Keep in mind, that this helps classes with larger hit dice a lot more, especially Barbarians. Also, are you assuming that HP is rolled, because this would do a lot more to help below average PCs than, say, wizards taking 4HP per level.
Also, if HP increases with level but HD don't, short rest HD will get less and less useful across the demi-levels. That's probably not a big enough deal to matter, but it's a consideration.
Spell Enhancement Slots
Some demi-levels grant enhancement slots, noting a level. An enhancement slot can be expended at the same time as the spell slot when casting a spell. The spell is cast at the level of the enhancement slot for effects that count the spell level, like dispel magic, and if it has increased effect at a higher level, it takes effect at the level of the enhancement slot, instead of the spell slot. Enhancement slots refresh when you finish a short rest.
This is cool. I'm not sure what the result of giving a consequential short rest recovering feature to the long rest classes would be, but I feel like its a good thing that would help harmonize the 5 minute workday and short rest classes.
However, upcasting is a really lumpy mechanic. Upcasting invisibility or hold person at 5th level gives you 4 targets instead of 1, but upcasting fireball at 5th only gives you 10d6 damage instead of 8d6. This changes the usefulness of a lot of spells. Tbh, the worst offender would probably be spirit guardians--its scaling is good enough that clerics already choose to upcast it in place of their 5th level spells (and I noticed you gave clerics a 5th level enhancement slot at 6+1, which seems tailor made for this). You would want to consider which classes/subclasses/playstyles get the biggest boost from upcasting, and decide if you're happy with that.
---
edit
another thought: since you are writing your own post 6 tables anyway, you might consider changing the spell slot progression, i.e. give casters a few extra 1st or 2nd level spells to pad out their resource depletion without changing their power level.