While I agree with the changes, in my view giving the hero dual types would have been a much more reasonable fix.
Orbweaver - Mystic/Elf
Deathknight - Knight/Undead
The other classes would be better suited with these changes too:
Assassin: Naga/Rogue
Archer: Elf/Rogue
Bard: Wildfolk/Fey(Elemental)
Dragonguard: Dragon/Knight
Knight: Knight/Human
Mechanist: Mech/Human (Cyborg!)
Necromancer: Undead/Mystic
Oracle: Centuar/Divine
Priest: Divine/Mystic
Runepriest: Dwarf/Mystic
Sorcerer: Daemon/Mystic
Titan: Giant/Elemental
Warden: Beast/Wargare
Warlord: Giant/Knight