I often use lamellar (half the cost of the heraldic mail), that can take 3-4 bodkin arrows easily, 2 if the speed bonus is really against you but mostly it isn't. Crossbows not so good, but I find it is more than adequate, as do a lot of GK who use it, and you don't lose any money with it I use steppe armour on less populated servers, but for EU 1 I always use lamellar due to the sheer number of stuff flying around. Khergit war helmet, leather gloves and nomad boots and you'll be fine. The helm you use is a bit pricey, the Khergit war helm is 5k less and provides plenty of protection.
Thing is, as cav your not supposed to take lots of hits. As long as you sustain 3-4 arrows you should be fine. If you get close enough to an enemy to be piked ect, then you would probably die due the the speed bonus regardless. And most cav don't get anywhere near that close, your job is to keep away and dive in when you see an opportunity. Not ride head first into the fight. The mistake many cav (myself included) make, is rushing into the fight to early and not waiting till your team is in melee with them.
you aren't completely wrong, but as 1handed cav(me) you do have to be able to take some hits, i know you play mostly as a HA, and with that class you don't have to have any armor really. i also use heavy boots, because i get hit in the feet a lot, i also have lemellar, which can take 3 hits before i get killed, i also use a destrier, because when you run into a wall or something, and you stop, and youre surrounded by 2-3 enemies, you want to get out alive, so they can usually strike 5 times or so, i can avoid 2 easely, but 3 still hit me and/or my horse, and if you have a courser or rouncey, or even an arab! you will never survive that situation. all the gear i have is chosen because of armor, my body armor, my horse, my foot armor even my head armor. yes, i know 52k is at the top of the
"making money-losing money" ladder, but it works best for me, i personally dislike the current upkeep system, because especially as cav, it can get you bankrupt in just a few hours. maybe it should be class based?