That's what Comeliness is, isn't it - a pure measure of attractiveness?
What I mean, is, he doesn't seem to use any of the mechanics associated with the score, simply using it as a gauge. Like say Intelligence didn't do anything mechanically , but you wanted a shorthand for saying "this guy is smart", so you said "he has a 19 Intelligence".
Huh. Cavalier was the only UA class we thought worth keeping; and its percentile-increment mechanic for slowly increasing stats as you level is pure brilliance: we applied it to all classes as soon as we saw it!
I never made Paladins a Cavalier subclass, though; I just kept both as equal sub-classes in the warrior group, along with Ranger. Our other main DM ditched Paladins and replaced them with Cavalier-Cleric hybrids.
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. Like, a character without a class is 0 level, but somehow these fellows start at level -2? If you want "apprentice levels" to be a thing, why only for one class? If you want to say "well, you can't start as a full Knight at level 1", so? The game has a concept of "name level" already. And if you are an apprentice, you shouldn't be adventuring, you should be following around a Knight as their squire. This isn't a unique issue- Unearthed Arcana was a lot of experimental ideas about how classes can work, like how the Bard, the Thief-Acrobat, and the Cavaladin are sort of previews for the prestige classes we'd get much, much later. Oriental Adventures and Dragonlance Adventures have other experimental concepts like the Ninja being a "half-class" and the ascending Solamnic Knightly Orders. It's not that I can't appreciate tinkering with new ideas, but this is one that sticks out like a sore thumb.
1b- of course, the sub-levels only exist if you're of low social standing. Because it's not enough that you have ability score requirements, you have to luck out and roll well on the social standing chart (a 20% chance) to actually be a level 1 character! Many words have been typed over the years about adventuring and nobles, but my main issue is that this is another "Gygaxian slot machine" like exceptional Strength or psionics to muddy up character creation. Oh and an NPC has to vouch for your lower class Cavalier. No idea what that entails- do I have to rp this somehow? Go on an adventure? It's totally DM fiat as far as I can tell...or flavor text, it's hard to be certain.
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.
2- race restrictions are always a weird thing. Why can race X be a member of a class but not Y? But right off the bat, we have Drow Cavaliers? Eh? Now maybe there's a setting or adventure where mounted Drow feature prominently that I missed (I mean, Drow have gone through a lot of changes over the years- I remember in D1 where they used javelins and atlatls, and who can forget that time Lolth had a male Cleric in the Moathouse of Hommlet?), but it seems a bad fit for a sneaky, Chaotic Evil, poison loving race. Yeah, Drow Rangers, I know, I know. But meanwhile, Duergar, who are at least Lawful and known for riding steeders, can't be Cavaliers? Huh.
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.
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!
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.
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:
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.
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!
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.
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!
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". So got an archmage hiding behind some ogres? Got to kill them ogres first! Unless you're playing bodyguard, then if they get in trouble, you have to rush to save them, no matter how many rounds of free attacks or other tactical considerations are required!
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!
Thus, the reason why despite all my nitpicks, the Cavalier is basically doomed. Many are the DM's who say "the world is the world" and don't segregate high level monsters away from low level characters. I've seen and heard about many "teaching experiences" over the decades.
But with the Cavalier, it matters not. You see a great wyrm red dragon? You're first level? Charge! No retreat, no surrender!