Minor nitpick: I really don't like how the generic Beastmaster Lord is better at buffing certain Monster units than Rakarth.
The only units Rakarth is better at buffing than the Beastmaster Lord are Kharibduses, Hydras and Harpies. Medusas, Black Dragons and Cold One units are much better under a generic Beastmaster.
Rakarth's unique trait of +8 Melee Defense to all Monsters is basically given to the generic lord as a skill. Which means he benefits from it while still having his own trait.
Rakarth's skill that buffs Kharibduses/Hydras is given in a partially worse version to the generic Beastmaster.
Rakarth's skill that buffs Cold Ones is given in a much better version to the generic Lord (+8 Melee Attack is much better than Stalk in my opinion).
Rakarth's skill that buffs Dragons is given in a better version to the Beastmaster (8 Melee attack is much better than 10% Weapon Strength in my opinion).
The Beastmaster also gets a Medusa focused skill that Rakarth is completely missing.
Yes, Rakarth gives Murderous Prowess to his Monsters, but the generic Lord also gets a Name of Power that can buff his Monsters even farther.
Overall, this feels like Rakarth is a sidegrade of a generic Beastmaster in terms of a Monster focused Lord when, in my opinion, he should be a straight upgrade.