So, in no particular order, here are my issues with the Cavalier. Some are minor, some are major.
1-introduce sub-levels that only exist for this class alone.
Another idea that can (and IMO should have) be expanded to all classes. -2 is overkill, but if a basic commoner is considered -1 then a trainee in any class* can be considered as 0th.
* - if you recall, there's an adjustment applied to your starting age based on what class you're in; I long ago interpreted that to mean that's how long it takes to basic-train for that class, during most of which time you'd be 0th-level.
1b- of course, the sub-levels only exist if you're of low social standing.
Easy to ditch, and make the same thing apply to all.
1c- Cavalier starting hit points. Ok, so this is kind of messed up. If you start at level -2 (0-level horseman) you have a d4+1 hit points (plus Con bonus). After earning 1000 xp, you earn another d4 Hit Die (but no Con bonus). As near as I can tell, you don't get more hit points for reaching level 1 (another 500 xp).
But wait! If you are one of the chosen 20% you start off with a d10+3+Con...for a class that presumably has 12-sided Hit Dice?! Yes, I know, Dragon Magazine later said this was an error and the class has a d10 Hit Die, but I didn't have that issue when I was playing 1e, lol. Still, the fact that it was an error means I don't need a 1d where I gripe about why this class has a d12 Hit Die, lol.
We changed them to a straight d10 hit die before ever realizing it was supposed to have been that all along.

The sub-level hit-point steps never made any sense, so weren't used.
2- race restrictions are always a weird thing.
With a few exceptions, I agree. The only species in my game that can't be Cavaliers are [Half]-Orcs.
3- On that topic, Chaotic Cavaliers always struck me as weird. I should point out you can be an evil Cavalier, but I don't suggest it. It's just bad.
And yet the "Black Knight" is a trope as old as time. They can't be CN or CE in my game, and NE or CG is a bit of a stretch, but anything else is fine.
4- Cavaliers are better than Fighters. The rationale here is that they train harder than lowly Fighters, I guess. This comes in a few ways. Adding your level to lance damage is in theory kind of busted, but I can let that slide- how often can you be on horse back, how likely you are to become a high level Cavalier, etc.. Cavaliers are better at the parrying subsystem. Sure, I guess. Cavaliers are +1 on the ol' combat matrix on horseback. Again, not a big deal. Cavaliers naturally get better ability scores as they rise in levels- hold up. What? So in a game where ability score bonuses are only allowed via magic (or in the cast of mental stats, getting old), here we have another "slot machine" mechanic that will let the Cavalier naturally go from 15 to 18 (00) in Strength, Dexterity, and Constitution!? Even breaking the good ol' race and gender limits!
See my previous post in response to Snarf re %-ile increments.
That they're better than Fighters (and anyone else!) in mounted combat is fine: mounted combat is uncommon, and comes with its own hazards.
Oh and hey, we're also immune to fear and have an aura that protects allies from fear, and of course Cavaliers have 90% immunity to many mind-affecting effects (but not high Comeliness, lol) and a +2 on saves vs. Illusions (because Illusionists need them nerfs, lol)! Cavaliers also don't die the same way as other mere mortals, being able to survive when reaching a negative hit point total equal to their 1st-level hit point total! They also get an extra d4 hit points back per week of natural healing. How? Why? Don't worry about it! Well at least they can't specialize in weapons, so there's that.
Other than the 'fearless' piece, we nuked all that. I did say Cavaliers needed toning down, didn't I?
But yes, 'fearless' is their biggest benefit.
If you've been following the endless debate about "nonsensical" Background Features in the "Do you plan on switching to 2024 edition?" thread (or whatever it's really called), then we have this fun tidbit:
View attachment 365177
Well at least it mentions political divisions so you can't hit up Strahd von Zarovich for free room and board in Castle Ravenloft, lol.
Another thing we largely scrapped.
4b- but hey, it's not all roses. We have a serious downside as well- for those first few levels, to level up we have to find a Cavalier 2 levels higher than we are, until level 6, when our normal training regiment is good enough to advance in levels, unlike those other character classes who need to pony up training costs and maybe even duel higher level rivals!
I have them train to level just like anyone else; but they do have to find someone 2 levels higher (all other classes just need someone 1 level higher) than the level being trained into.
4c- Cavaliers are super good at mounted combat. This isn't really an issue, I mean, this is their schtick. The only eyebrow raise here is 4th level elven maidens being able to ride unicorns. As expected of a mounted class, your warhorse is just better than everyone else's- not only can you look at a horse and know that it has higher than average hit points or not, just for riding it, your mount gets 2 more hit points per Hit Die...but not over the maximum hit point total. Ok sure. And yeah, at levels 7 and up, we have the option to ride increasingly fantastical and flying mounts, but I'm not sure you're going to hit that level anyways.
I can't remember the last time I DMed a Unicorn.
It's a standing joke here that a Cavalier's warhorse is usually as or more Intelligent than its rider.
5- Cavaliers have strange thought processes. Gotta have full plate armor. What, you got Field Plate +3? Nope, gotta chuck it, Full Plate +0 is obviously superior! But wait, it doesn't stop there!
View attachment 365179
Yes, that's right. In combat, you don't get to run your character, you have a pre-programmed script you need to follow. Doing this ensures that you always rush the strongest foe on the battlefield before being allowed to take on "lesser foes".
And this is what makes them fun to play - they come with built-in gonzo at no extra charge!
And then there's your Code of Conduct. Now, the one given is a sample. The DM can make their own. But when I saw Cavaliers played, the DM's apparently went with the example. If you violate your code, you can earn less, or even no experience points for doing so. And the sample code basically says you would rather die before dishonoring yourself, and of course, running away from a fight is dishonorable!
I kept the codes of conduct for Paladins but toned them down greatly for Cavaliers. The main remnant is that a Cavalier will always seek to defend members of the opposite gender.
But with the Cavalier, it matters not. You see a great wyrm red dragon? You're first level? Charge! No retreat, no surrender!
Ayup. What was I saying about built-in gonzo?
