Cav were more seen in the old AOE for three reasons.
1) The cav powerhouse Yam was faster in AOE than ROR because then its vils were 36% faster vs 18% now.
2) Scythe due to their area damage really hurt bunches of cav/Hcav in the iron age. Scythe cost no gold, while cav civs often run into gold shortages or find that they lack gold for other units do to making and losing a bunch of cavs. People are making more chariots now in bronze and using them to fight because the ones that survive will upgrade to scythes for many civs. Also camels have less bonus vs chariots than cav.
3) Camel w/+8 atk just eat cav up. Let's look at a basic battle in early bronze. The "mel" does 14 damage to the 150 HP cav which in turn does 8 damage to the 125 hp mel.(both have same ROF and assume armor/atk upgrades cancel out)...well in 11 hits the poor cav goes to the "Big Glue Factory in the Sky" ..while it takes the cav 16 hits to kill kill the camel. Camels also take 30 sec to build vs 40 for cav. Mels cost the same food as cav but require 20 less gold to make.
What about cav's good aspects ? They are better vil killers than camels although if you have a few of either of them among your not yet bronzed vils at 15 min you are screwed either way. In earlier bronze we assumed that we only have tooling and horse armor. Tool working means that cav now do 10 damage and kill vils in 3 hits, while chariots do 9 damage and kill vils in 3 hit,, however mels do 8 damage and require 4 hits. The addition of metalworking (not cheap) allows mels to kill vils in 3 hits. So cav are in general a little bie better at vil killing.
Cav's are tougher and more likely to penetrate a hail of arrows and take out enemy ST than are camel or non scythed chariots. They are clearly better at hacking compies up. (Note that hcav get piercing armor not normal cav)
One of cav's best points are it's NICE +5 atk vs infantry (not slingers). People love to tool rush me and I love it when 3 cav kill 10 of their axers later. Cav are better vs slinger too since they kill them quicker and can take more damage.
As far as iron age cav go.. well the cataphract upgrade is the games most OVERPRICED. Let's think you spend a ton to get 2 more armor 2 more AP and 20% more HP. Let's compare to the costly cent upgrade. Well you get 33% more HP, 1 more armor and OMG!! 10 more AP. As it is, the cataphract upgrade should cost about 1/3 of what it does, IMO. Or the cataphact should have the following specs. 240 HP, 3 armor, 3 piercing armor and 14 ATK to be worth it. (OK maybe I am overdoing it a bit here.. but you get my point.) The cataphract upgrade is even more overpriced than jugs or ball towers.
What about Hcav ? ( I laughed my butt off last week when an enemy had 3 of them )That upgrade costs 350 food , 125 gold and for 475 res he could have made 3 more cavs. The Hcav has only 2 more AP than cav along with a bonus of 1 armor and 1 PA. OK 25% more AP and a small bit of armor. That PA will help vs left over CA/compies however... can we say that Hcavs are as good as 1 1/3 cav ? Well 4 cav beat 3 Hcav in battle due to numerical effects (2 cav kill one Hcav while the other 2 cav are still alive) However, the Hcav are better vs arrows.. so .. I guess I'd rather have 10 Hcav than 13 cav but not certain. One thing seem certain and that is that I would not upgrade to hcav unless I had at least 10 cav allready or were certain that I was going to be making alot of cav in iron. So basically the only civ that might do that is Yam.When I fast brnze rush I am more likley to hit w/mels first since I can make them 10 sec faster and that might make a difference. I send in a couple of waves of mels normally rather than cav. However, I may make a few cav later and having them with later armies as they are clearly better vs compies and ST.
Cav aren't bad but my 3 reasons above are why you don't see too many in ROR...neilkaz..