It's a lost cause to appeal to common sense my dude. Because even me giving actual proof of cavalry charging directly was not enough to convince Hruza,
he just keeps repeating the same party line he's been obsessively repeating for, literally, 6 years. If proof won't convince him, common sense definitely won't either.
Adherence to history shouldn't take precedence over fun, that is entirely true. I am just trying to make the point that the fun way is also fairly historical.
And yep, melee cavalry are high effort for low reward compared to the other options right now.
By release, melee cavalry should fulfil the battlefield roles of outright slaughtering any infantry who do not have braced long pikes or a shieldwall, flanking distracted formations quickly, and inflicting morale damage through frontal charges. On average, they should go even in a fight with shieldwall infantry, ranged infantry, or ranged cavalry of the same tier and quantity. Weaknesses should be braced long pikes, tricky terrain, and losing some effectiveness in sieges.
With
all of these roles, cavalry will be worth their higher cost, will be balanced relative to other options, will be fun, and will represent their real historical role well.