Ugin, Eye of the Storms' first ability makes him incredibly obnoxious as a commander for Brawl. He would be a lot less infuriating to play against if his first ability were changed to trigger on ETB instead of when you cast him. A better change would be to restrict Planeswalkers as commanders to those who are printed with the ability to be a commander, but since that probably won't happen, this seems like an actionable fix to one of the more annoying examples.