Is my Elephant Shield item balanced?

I created an item which is, conceptually, a hybrid of the Arrow-Catching Shield and the Ring of the Ram. Both of these are rare, however my item has some more restrictions, so I’d class it as uncommon. It was created with a 5th level fighter in mind.

Elephant Shield

Armor (Shield), uncommon (requires attunement by someone with a strength score of 16 or higher and proficiency with shields)

This shield has 3 charges and it regains 1d4 – 1 expended charges daily at dawn. While wearing the shield, you can use an action to expend a charge. Make a melee weapon attack against a target within 60 feet. The attack appears as a spectral elephant and deals 2d4 plus your strength modifier as bludgeoning damage on a hit. Also, while you wear the shield, you can use your reaction to expend one charge and add 2 to your AC against one ranged attack that would hit you, provided that you can see the attacker. Additionally, whenever an attacker makes an attack against a target within 5 feet of you, you can use your reaction to become the target of the attack instead.

Some modifications might look like oversights but are deliberate:

  • Using a d4 for recharge
  • Inability to use multiple charges on one attack
  • Third ability extending to melee attacks
  • Third ability not using a charge
  • Proficiency requirement (seems reasonable for the third ability)

I am interested in whether this item is balanced, specifically if it is (a) obviously abusable, (b) wildly inappropriate for level 5, or (c) ambiguously formulated.