If we assume that both mana flood and mana screw are things that we'd like to avoid in order to have a fun game of Commander (and maybe even a chance at winning the game), then adding more MDFCs to your deck during deck building is the perfect solution to the problem
Rotation sees older sets leave the available pool of cards, and used to happen on a yearly basis
The set introduced role tokens, and has other great cards such as Stroke of Midnight, Blossoming Tortoise, Agatha's Soul Cauldron, and a cycle of strong virtues
There's nothing inherently superior to Mox Jet over Mox Sapphireit simply provides a black mana as opposed to a blue mana
Grading Magic Cards Guide to Magic Card Grading This guide lays out how Three for One Trading grades Magic cards what each condition means, why EU/US terms sometimes clash, which tools their team uses, and how multiple checks keep mistakes rare
United Front United Front and United Battlefront both printed in the same year is a minor annoyance Ill get over