Griselbrand is still fairly new and as such getting all the novelty play and while perhaps the better card overall he is just worse at the card side of things than Bargain and so doesn't make this list
The combination of self-mill, ramp, and board presence drips with power and makes this a frontrunner for graveyard decks
Now add in Swords to Plowshares, Squirrel Nest, Altar of Dementia, Spiritmonger, Silent Arbiter, Mirari's Wake, Victimize, Ill-Gotten Gains, Stifle, Brainstorm, Rout, Pristine Angel, and even Edric, Spymaster of Trest
Meanwhile anytime a foe drops a land, they give you two cards and exile two of their own
Budget deckbuilding does not have to be that difficult, especially for a format like Commander
There are only a handful of Commander decks where card draw is a key mechanic rather than simply an advantage and a way to get slightly ahead