Its +1 ability will let you get even more loyalty so long as you have creatures that can attack
This means that you will probably be drawing an extra card every single turn
Dont Forget: Songs can be summoned by spending ink, or by exerting a character who is of an appropriate ink level, they are then used instantly
The creature can be destroyed if any of those elves has a part of their head higher than the bar
Myr Enforcer may only be a 4/4 but you can often make it for nothing on turn two which makes it wildly better than a 2 mana 5/5 even without the drawback
Balance the deck with 36-38 lands, 8-12 ramp, 8-12 card draw, 8-10 removal, 2-4 board wipes, 2-4 win conditions, and 25-30 synergy cards that support your commanders plan