Its about structural integrity, not just style
As a commander, Kefka can be ruthless, forcing your opponents to discard cards and sacrifice their permanents (whack a Tergrid in here to be extra mean)
In some decks, this card can completely stop the opponent from setting up their game plan, but other strategies have ways to work around it
Attunement 6.5 This is a very heavy discard outlet
Obviously these may be a miss for your format for other reasons (power, archetype mismatch, rarity, don't run planeswalkers etc) but here's a few that I found interesting, divided by broad category rather than color: Actual Modal Dual Faced Cards: While I'm still not done reading Cosima, God of the Voyage (I'm on chapter 2, the language is a bit dense) these cards are ones I do like both sides of