Both Guildpact and Dissension have some powerful commons, but they are localized to only a few color pairs: UR and BW in Guildpact: UW and UG in Dissension
Its really just further exploring that same false equivalence: that all creatures, or all permanents, are equally valuable
In the Commander variant, a meld card's color identity is determined only by the mana costs and mana symbols in the rules text of its front face
As long as Souls of the Lost is in your graveyard, that ability will count Souls of the Lost itself
They may have a few powerful cards or interactions, but many flaws can be improved: weak cards, poor mana bases, and high mana curves
The name of the card is also imposing, the art is beautiful, and the flavor text is dangerous and foreboding in a way that keys the audience in on the abolishment edict to come