Arcane "Execute" Ability
I'd like to see a warrior-mage hybrid ability that replaces Execute with something that does arcane damage. Instead of converting rage into additional damage it uses your mana instead. If you have 15k mana and can execute the target then you can use this mage ability to deal 100% weapon damage + ~15k arcane damage.
...But then you're out of mana so maybe limit it to half of your current mana to nerf both the maximum dmg output/mana usage