One of the things that bugs me and my GM about the Psychic Phenomena or Perils of the Warp table, is it's an incredibly polarized table. With only a few exceptions almost everything in the table does either so little as to be trivial ("Oh no! The walls are bleeding. This changes nothing regarding the charging Ork in front of us, and he's burnt to a crisp by your Fire bolt.") or practically an instant-death sentence, with very little in between.
It's kind of.... frustrating for at least my GM and myself to an extent that, the vast majority of the time, the Phenomena either may not have happened at all, or it just wiped the party. So I figure it might be interesting to make some homebrewed Phenomena. Stuff that won't necessarily result in a TPK, or absolutely nothing happening, but rather cause either annoyances or inconveniences for the character, if not at least something the GM can have some fun with. Vice Versa is a good example of something like this, imho.