Since youll pay life rather than mana to cast opponents spells, youll need lifegain effects, something that black cards have plenty of: Gray Merchant of Asphodel or Sheoldred, the Apocalypse balance out the life costs for casting opponents cards you exile after combat damage
Similarly, while it's unlikely we'll "unbuff" cards that received balance adjustments to improve playability (and currently have no plans to do so), only a certain type of dark-empowered entity deals in absolutes, and we're not them
Of course, thats a bit of a more out-there version of how this card could be used
Even as power creep shifts the meta of different formats, Angels remain some of the most powerful tools competitive Magic has to offer.
That Food conversion effect is most relevant for Ragosts second ability, mind you
Group hug theme