The buff Don Andres gives to stolen creatures as well as the Treasure tokens he generates when you cast noncreature spells that don't belong to you are nice, but they're far from enough to make stealing cards worthwhile (especially because the treasures enter tapped)
While you do have to wait for these abilities, the amount of value you get for literally nothing is obscene
The Gold Star Charizard, in its black delta-species shiny form, hit $100,000 in PSA 10 in February after $65,600 in December, roughly tripling in six months
You can use it with Solemn Simulacrum or Ichor Wellspring for little value plays, or sacrifice and reanimate a Portal to Phyrexia to devastate your opponents
There are potentially better planeswalker cards with more consistent and powerful effects for competitive play, but Dungeon Master could be a fun and flavorful inclusion in casual or themed decks