I'll do this point by point.
1) Yeah, that was an opening statement. The rest of the post attempts to explain why. Also, class comparison isn't a particularly valid way to argue this, since cav aren't retarded enough to try to fight pikemen or foot archers alone. They just run away and go kill other people (I know I do). Horse archers are a slightly different situation - yeah, as long as they have arrows and aren't retarded, they'll beat other cav.
2) cRPG isn't an organised battle. Most players on any given map are not in clans. cRPG should definitely not be balanced by letting good players fight each other. 'Bad' players (new players or players who cba to dedicate the time to getting more skilled) should be able to have fun too.
Also I don't understand what you mean about life being balanced like that, so I'll ignore it.
3) Yes, true. The ability to have a pike as part of your standard loadout (for everyone) also kept cav in check. Also, I never mentioned anything about HA being able/not able to counter other cav. And as I said before, ranged do fine against cav, I agree.
4) Yeah, true, I didn't distinguish between types of cav. As I said at the end of the OP, none of it addresses the issues of weapon type on horseback (lance cav/1hand&shield cav/HA/2hand cav/xbow cav/jav cav). HA and melee cav are different, but they all share something in common - they use a horse. And my suggestions were all horse related.
As for cavalry being underdogs on foot, I don't see how its obviously true. I do fine as infantry. I put 7 points into riding - what else would I have put them in? Ironflesh? Or converted a few for an extra point somewhere? Sure, I'm very slightly at a disadvantage vs someone with more ironflesh, but all that means is I have to block better.
Most (if not all) of the top cavalry players do very well as infantry too.
5) Well, no. You can't say that for any class. The problem is that you don't have to be good at cav to get very high scores (until a good cav comes along and out-lances you). The only other classes I've seen able to sometimes match cavalry kills are 2handers or polearms (mainly using long polearms or one of those silly greatswords). And that doesn't happen often, and usually only for good players.
And once again, cRPG shouldn't be only balanced around the best players. It should aim for a situation where every class is fairly difficult and requires a level of skill to do well. Cavalry doesn't do that at the moment.
Edit: sorry, you edited
The numbers refer to your points, not your numbered replies.