Let's talk about cavalry

[Ibrahim]

everybody loves light cavalry interesting

so am I only one who is mad about elite and expensive cataphracts?

Kataphraktoi tire too esily. they're good, even great, but they tire easily. Heavy cavalry is not as good, but they are less easily tired out, hence more effective charges. Its like using a normal hammer vs. a sledgehammer: you can hit mre often with a normal hammer than a sledgehammer, and you are less tired. It also requires that you get it right the forst time you charge.