Leech Seed is generally better for Sturdinja. It KOs it through its Lum Berry and it isn't blocked by Safeguard.
The Auto-Crit moves aren't powerful enough to be worthwhile as you can just pick a the strongest moves of each type. It might have some use against defense boosters but it doesn't seem worth an ability considering there are better options (i.e. Heart Swap or Phazing Moves.)