Races: There are
too many races in your standard D&D world, too many races indigenous to too small of geographical regions, and there's far too little distinction between them to go around. Doubled and tripled for the utterly unnecessary
subraces. AD&D Specific: the majority of officially published AD&D player races had the exact same class and multiclass selection as Dwarves; only the
very weird campaign settings with the
very weird races (PS, SJ, DS) substantially broke from this mold, and even then
subclass access remained relatively rare.
Multiverse: There are a lot of
incredibly specific, niche, obscure, weird, and
not particularly relatable cosmological assumptions built into the D&D rules that are then imposed upon the majority of officially-published D&D settings when they are not thematically appropriate to that setting. In some case, they are not thematically appropriate to
any setting, but they're "part of D&D" so they have to be shoehorned in.
For a brief overview:
- Alignment: In the interest in not rehashing old arguments, everything about alignment bothers me and I wish it would go away entirely. I will say, however, that the idea of moral principles as literal metaphysical forces is something that occurs in a very small proportion of the stories that D&D is based off of, and an even smaller proportion of the stories people want to portray in D&D.
- Cosmology: I love the Great Wheel Cosmology, in both the Greyhawk setting it was derived from, and in the Planescape setting that was derived from it. The Forgotten Realms setting had its own cosmology going on, and the Dragonlance setting had its own cosmology going on, and these settings were lessened by having their own mythologies and afterlives homogenized to make them fit into "the multiverse". I love the World Axis cosmology, too, except for the Forgotten Realms having been folded, spindled, and mutilated-- again-- to be made to fit into it.
- Theology: The standard D&D assumption that the gods feed on mortal worship and are only as strong as mortals' belief in them is an incredibly monotheistic approach to polytheistic religion. And it's a good setup for a maltheistic world where mortal heroes oppose the malignant divine. It's not a very good setup when Good and Evil are objective moral forces, and the "Good" gods work to uphold and preserve the system that empowers the Evil gods, and mortal heroes are expected to uphold and preserve that system too, or else.
- Religion: There's a "pantheon" of gods spread across the whole world, who each have their own portfolio or special interests... except they're all unrelated to each other, they don't have any shared origins, and they're all rivals for mortals' delicious prayers. Regardless of their ethos or their portfolio, they're all structured like medieval Catholic churches and they all behave like Midwest tent revivals. The one thing they do not resemble, in any way, is any pre-Christian or indigenous religion I've ever heard of.
I don't think there's
necessarily anything wrong with any or all of these assumptions in a D&D fantasy world... but it
bothers the hell out of me that they're
all present in the majority of official D&D worlds and most people don't seem to have the slightest inkling that this isn't just what "fantasy worlds" look like.
Mechanically... a broad overview:
Race: I started with AD&D, so this is pure hindsight, but it bugs me
how little difference race makes compared to class in AD&D onward. Some ability score adjustments/restrictions that don't matter (unless you're playing a half-ogre or something) and F/C/T/FC/FT in AD&D, fishing for +2 to as many of your prime and secondary requisites as possible for your chosen class in WotC/Paizo D&D. Somewhere in the low single digits, your
biological and/or
mythological distinctiveness simply stops being a meaningful part of your character's function.
Multiclassing: It still
really bothers me that after four years of trying to fix 3.0's multiclassing system in 3.5, and abandoning it entirely in 4e, they simply re-adopted it wholesale with few, minor, alterations in 5e.
Hit Points and Armor Class: I actually like these as written, and lean into hit points intentionally by saying they
really are "meat points", a measure of how much punishment a character's physical body can take and keep functioning. What bugs me is that people keep trying to
fix AC by turning armor into damage reduction and making the game
less realistic because the relationship between weapons that have big damage dice in D&D and weapons that can effectively damage someone in heavy armor in real life is
exactly reversed.
Armor: The only armor penalties in D&D that are even
remotely justified are stealth and swimming. Reckon I've known a lot of men and women with Heavy Armor Proficiency, courtesy of various martial arts and reenactment groups, but I suspect I've still never met a single 7th level Fighter... yet I've known quite a few people who can reliably hit a DC 15 Tumble check in non-masterwork half-plate and field plate.
Proficiencies & Skills: I feel like these could have been a great idea, if they hadn't started by
limiting what normal characters could previously do. Guarantee you I'm not a Fighter or any Fighter sub-class, and I'm probably not more than 3rd level-- if that-- but I'm solidly, demonstrably proficient in more weapons than a name-level Fighter in AD&D. And fewer than any cherry private or rookie patrolman. Particularly egregious when a high-level Fighter in magical plate mail (see above) is
helpless in the face of a 1st level Wizard's
grease spell because he didn't invest any of his three skill points per level (why?) in Balance.
I can't do anything heroically or preternaturally well, but I am
basically competent in more things than any low-level D&D character, and aside from a couple specific talents, I don't think I'm some kind of Renaissance Man compared to other people. (Definitely a Bard, though.)
Two Weapon Fighting: Fighting with two swords doesn't work that way. Fighting with two guns
especially does not work that way.
Ability Scores: The ability score cap in 5e bugs me. One, it means that despite every race just boiling down to "the one with the +2 I want", everyone's going to end up with same ability scores by level 12 anyway. Two, it means that the pinnacle of human(oid) development-- pre-
immortality-- is acheivable at 4th level.
Bounded Accuracy: It's a great idea
in theory, but in execution it means that your capped ability scores and your fixed proficiency bonus
probably aren't going to change by more than five points for most of your skills from 1st to 20th level, so you're only
marginally more effective at doing the
exact same stuff at 20th level then you were when you rolled the character.
Honestly... more of my little "it just bugs me" problems with D&D come from people trying to fix what just bugs them than from what's in D&D itself.