Queen of the Undead

Irresistible presence. Due to your overwhelming presence, undead creatures are less capable of resisting your influence on them. You gain the following benefits:

• An undead creature must have a WIS of 12 or higher or it cannot gain advantage on its saving throw to resist your control.
• When an undead creature makes a saving throw to resist your control over them, you add your Charisma modifier to the DC of the saving throw (minimum of 1)
• If you use your action to use the Command Undead feature, you may target an additional undead creature as a bonus action.

Improved minions. All undead creatures who are friendly to you and who are obeying your commands gain the benefit of your Undead Thralls feature as though they were created by you using a Necromancy spell. 

(Optional - ask your GM) You know the Consume Thrall cantrip.  When you cast this cantrip, you choose the number of hit dice which are consumed from the target creature. Creatures which would stop obeying your commands when you use this cantrip on them do not do so unless they succeed on a Wisdom saving throw.