How good is the UA Hexblade for Gish Warrior + Blaster?

[Ravinsild]

The character concept is as old as time, you've seen Game of Thrones, or Vikings or The Last Kingdom and many many other media depicting the Warrior wading into combat with 1 sword in his hand and either a shield or no shield deep in the fray hacking left and right, slaying all enemies around him. Then just add magic to his "Off-hand", like a Jedi or Sith, as said Warrior is hacking and slashing and gaining glory for valhalla or whatever, an enemy charges toward him and...he blasts him in the face with a fireball (like Endeavor or Todoroki from My Hero Academina or something).

How good does UA Hexblade + Blade Pact Warlock do this concept?