ok what the hell is a hemomancer that's the stupidest name I've ever heard. A hero should be named by what he is, what'sl his role, his story bla bla..and not give him a set of random abilities.
Paladin - is a defender of innocents driven by light and honor, an upgraded version of the knight if you may...Holy light, Divine Shield, Devotion Aura and Resurrection, all these abilities go for him because of what he is and what he represents...also you shold think about the model, the attack range (Divine Shield goes very well for the Paladin as he is melee so he needs something to protect him and not become a punching bag or get sorrounded). Understand ?
Blood Mage - Prince of the high elves of Quel'thalas, named after him murdered brethren...His abilities Flame Strike, Banish, Siphon Mana, Phoenix are all perfect for him as he has only rage and vengeance in his heart, embracing the dark magic of the demons to bast Banish like his original bretheren the Sindorei, 10000 years ago when the Well of Eternity still existed. And now with their homeland destroyed and becoming separated from the source of their magic, the blood elves hunger, thus having the ability Siphon Mana. Also it is mentioned somewhere in the lore that Blood Elves have the ability to summon Phoenixes from the beyond to aid them in battle and are a reflection of the blood elves as they once died and revived and are constatly consumed by their burning hunger for magic. So think before you make a hero randomly.
Peace.