As for lands, theres another set of eternal night lands, continuing the theme begun in Midnight Hunt
However you leverage these effects, they ensure you get the most of your creatures from birth to the grave
Since Silverquill, the Disputant naturally encourages a more aristocrats-y approach to tokens, sacrificing them for value, it's great to have a card like Sedgemoor Witch, that keeps spitting out tokens which themselves give you value when they die
In Modern that plays out as a fast clock that fights through attrition naturally, and in Commander the graveyard synergies with any sacrifice or self-mill strategy are a natural fit
Background looks to play around in that space a little more, opening up the possibilities a little more than Partner with without going full on into Partner territory