While Faithless Looting isnt the best when it comes to card advantage, and casting it will always leave you down a card
If you play any of these two cards in a casual, fun way, then there is obviously no problem -- but what do you do in the competitive environment
Just in Mono Black alone I'd say Yawgmoth, Thran Physician is a better Sacrifice commander, and once you start adding additional colors there's Meren of Clan Nel Toth, Teysa Karlov, Marchesa, the Black Rose, Korvold, Fae-Cursed King
The Titan alone can ramp you from 6 to 8, but the land tutoring has many implications in different formats, since you can choose between Slayers' Stronghold, Field of the Dead, or Valakut, the Molten Pinnacle, using your various lands as a toolbox
And, hey, Mystic Decree is a world enchantment