The only thing that needs fixing is the prelate. The rest isn’t even remotely as bad as a lot of folks make it out to be.
If the prelate works as intended, every other unit will get properly boosted. Landsknecht fulfills the job as a glascannon. MAA fare really well against knights and other MAA, actually outshining royal knights in a per ressource comparison.
Culverin help with opposing siege, ranged infantry get the speed buff giving them a better ability to kite.
Regnitz gold is actually insane, feudal MAA help securing the relics pre castle age. And we shouldn’t forget about emergency repairs which at least I have used to great extent.
I would agree that the civ needs some work done, but not as drastic and urgent as you guys make it seem.
But in direct comparison to the likes of Delhi and China for example, HRE does very, very well.