I agree that the 1-20 sever is a blast even with my NA ping, however I don't think No horses is the answer to everybody's problems. I think I have 5 gens of cav atm and my clan has a lot of cav but we cant roll a server 100% of the time.
To simplify things think of the game as having at its core 3 general roles - Infantry, Ranged, and Cavalry any large over population of the three will destroy destroy not because of any Op'ness but because there isn't enough of the counter role to balance them. If you dont take the analogy too far its a bit like rock, paper, scissors ( okay so its a really thin comparison, because of the large variety of builds and I don't remember the rock ever being able to take out a pair of scissors, and the games closer to rock, paper, scissors, lizard, spock but bare with me its just an opinion) Cavalry will avoid a archers nest like the plague the same way most infantry with good reason should avoid cav. The long sword or 1h axe, etc is not a swiss army knife that can do everything nor should it be.
I'm going back to archery for a few gens and I already want Agi builds to go roll around in rusty nails but I see that a " 4 maximum athletics sever" would be crazy pants.
Hmmm this was a really round about way to say use teamwork and know your role. or join siege which has everything you asked for except it will still have 30+ builds