Cards like Atraxa, Grand Unifier, Tarmogoyf, Reconstruct History, and Nethergoyf increase in effectiveness the more card types you have access to, so including a few sorceries helps unlock these cards fullest potentials
This leads us to another rule: 4
For Starving Revenant's enters-the-battlefield ability, you put cards into your graveyard for surveil (if any) before drawing cards
The ones I listed do vary in power level, some definitely not at the same competitive level as the ones you mentioned, but I believe having a card speed up any combo general by three turns is not something to be underestimated with
The limited number of cards in circulation, combined with Sakazuki's significance in the storyline, makes it a prized collectible
Along with weight training, Rodriguez also grew out her armpit hair