The Hero's Path

I played as a Knight, with a composition of archers, druids, fire elementals, and Knight Isabel. I thought it would be difficult without ranged damage dealers. I started playing again as a Warlock. The start is tough; you constantly run back and forth to compensate for morale because there are no high-level dark units at the beginning, and the lizard riders don't survive battles against the hero. But once I reached the elves and managed to break through the guard in front of the chapel with the dark mage, it became easier. I sold all the light units, recruited dark riders, got seductresses, and started recruiting vampires. It's going well. Later, I can probably add some death knights.
Hero + extreme difficulty. Without extreme difficulty, the start would probably be easier, perhaps with rogues. But that's not certain.