As things stand, cavalry works in cRPG. Within the rather complicated framework of awesomeness and balance that is this game, it fits. It has its counters, and it has its advantages. However, I think that the way in which it fits into the balance puzzle of cRPG is somewhat fucking stupid.
The most successful (melee) cavalry players fight using two items: the heavy lance and the courser. They rely on speed and suprise to defeat their opponents, sneaking up on them like the god damned batman. Ninja batman. I speak from experience, and from information gathered from other players, when I say that this is annoying and homomsexual (in a bad, rapey way, not the rainbow way). There is little satisfaction on the part of the ninja-lancer, who gets his kills not in a straight-up fight, but by lancing people in the back. The victim feels rage-tastic, because in the two seconds he took to pick his nose or finger himself he got killed by a horse swooping out of nowhere. Silently, for horses are silent predators apparently.
The few 1h/shield--or even, gasp, 2h--cavalry players that exist get their kills in a similar way. Though if they're not sneaking up on people, they're probably bump slashing them. That's another issue, though, for another suggestion. One which will also be completely ignored, just saying.
This situation is made even more fucked up by the relative softness of horses, and prices. The ninja style of play, whereby cav swoop out of nowhere and avoid direct confrontation (or, when they have to fight 1 v 1, they stay out of range and poke w/ heavy-fuck lance), is "balanced out" by low HP amongst the only affordable horses in the game. The courser dies in four or five arrow hits. The destrier is, perhaps, a bit stronger, but is still rather fragile. This causes rage on the horseman's part, for obvioius reasons.
Disregard the high-tier horses in this discussion, due to their extreme price. I remember the days of the tank horse, and I don't miss them. Still, high-tier horses are simply too expensive. And the affordable ones, the warhorses, simply suck.
I likely echo the feelings of many cavalry players when I quote my bitching self:
"I very much dislike having to use speed and suprise to kill my enemies, stabbing them in the back without them even HEARING ME. I also dislike having to resort to expensive metal horses in order to close with and kill my virtual enemies fair and square (or try to, given their softness). I dislike the idea that the best horsemen use the heavy lance, ride the courser, and have to fight like absolute pussies. I dislike not being able to charge into the flank of an enemy gaggle-fuck with my comrades in arms and cut bitches. I also really (really) dislike my horse dieing in three or four arrow hits--perhaps alot "realistically", but not in the world of cRPG."
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So, wat do? (Actual suggestion)
Buff/nerf horses, of course: switch up the stats "balance". Increase horses HP, but decrease their speed/maneuver. The speed needs a heavier nerf than the maneuver, but I think maneuver is a bit high. Simple, right?
Decrease the price of high-tier (metal) horses, and SLIGHTLY boost their armor (note that I didn't suggest to boost mid-tier horse armor, just their HP). Keep the plated charger's price, though: it should be a godlike tank of destruction, but expensive.
Boost horse charge, to promote epic charges, of course. (Debateable suggestion)
MAKE HORSES LOUDER, if possible.
Pretty please with cocain on top.
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tl;dr-- Go fuck yourself. Or see the bold stuff, for I am a kind and understanding OP.