Angels and paladins – how to use them? There are also discussions about them here.

Let's go through everything in order... First, if Seraphs were given vampirism, it would be overpowered, in my opinion. I remember installing a mod for Heroes that replaced the standard human upgrade in Warlords with the current one (although there are many differences between them). For example, 20 Seraphs with Blessing and Stone Skin + Vampirism would be too much... So, the new angel upgrade might not be as strong, but at least it's fair, in my opinion. Second, does anyone actually use the Griffin upgrade? If not, I'll say that they're not weak at all. Here's why: I recently fought a duel with Vittorio against Axel (I went first)... He killed almost all of my army except for the Griffins (they were flying). At the end of the battle, I had 6 Inquisitors, 40 Archers, and 40 Crossbowmen, and he had everything except horses and Archangels. I cast Stone Skin on the Griffins with the Inquisitors, plus Blessing, which I had cast earlier, and then I cast Vampirism... 70 Knights were killing 4 Griffins at a time (the Knights were under Blessing and Power Strike), but the Griffins kept dealing more and more damage, and their numbers didn't decrease. As for Paladins and Archangels, I think the new horses are better - they often have to attack from two squares away, and they deal more damage. You send them into battle right away, and the Archangels heal, that's all. Once again, in my opinion, the Seraph is not meant to support Paladins. Sometimes it can hit even harder than Paladins, and Divine Retribution is a powerful spell, even though it requires sacrifices from your own army.