My favorite solution to this is to come up with fun, never-before-seen combos
Phenomenon cards, after their effects have taken place, then require you to Planeswalk once more
See the future and cast miracles with Miracle Worker, fill your graveyard and reanimate monsters with Death Toll, cast tricky instants and mysterious face-down cards with Jump Scare!, or control monstrosities and make your opponents pay with Endless Punishment
Certain fan-favorite mascots and cards tend to have a higher value than others
Ranking the 20 Best Interactive Blue Spells in cEDH Ive built a lot of blue cEDH decks recently, and they generally all want the same interactive spells, so I just have to figure out how much blue interaction I have, and then I just fill from the best down, so I thought Id share my list and reasoning, as well as where I want to deviate: 20: Spell Pierce Interaction in cEDH needs to be extremely cheap