The push-happy Blood Angels librarian in my current campaign has finally triggered the insta-death option from the peril of the warp charts mid-mission. My method of GM'ing is more focused on the everyone having a good time so I am not extremely strict in following the rules. Due to the player being attached to the character and his tendencies of making the missions more interesting (I believe the daemon prince summoned tracker is nearing 15) I decided to go with an alternative to simply having him make a new character. On top of burning a fate point he was given 3d10 corruption and insanity, 1d10 permanent damage to two random characteristics, and a random mutation from the gift of the dark gods from BC. In addition his character suffers the effects of lost to the warp and will automatically trigger the perils of the warp chart in any event perils are triggered. Overall the character gained 23 corruption, 12 insanity to gain the first stage of the primarchs curse, 4 damage to FEL, 2 damage to WS, gained the warp-touched mutation (Entropy), and played a large part in the failure of the mission. I do plan to have the Assassinorum and Inquisition be heavily involved in the future due the effect of lost to the warp as sabotaging a very high level Ecclesiarch would tend to do bring them into play.

tldr;

Throughout all this I was wondering what other alternatives has the community applied to their respective games or is RAW strictly followed in your campaigns with the psyker being irrevocably destroyed.

To be honest, in our DW group psychers are the most short-lived characters at all. Only xenos and heretics die faster.

In my BC game i use a rule I call warp churn: Every roll on the phenomenon table adds +5 to the next roll. Every perils roll adds +10. This had largely had little actual effect, but has put tremendous fear into my psykers of actually pushing.

The GM always has the ability to override anything in the table and just because it says its that terrible 00 result then it doesn't mean you have to go for it. You can easily sub the result for something more appropriate to the plot.

Despite the book saying otherwise I have rolled a 00 as well when I was a push happy librarian and didn't get obliterated...my GM resolved the power back on my own character with a negative effect and basically smashed my characters soul and conscience out of body for a while. In that state I could only observe the field around me, see things which were perhaps there and not there, see my own body bloodied and almost broken and do nothing about it. The effect is quite terrifying to have an out-of-body experience when you get put back into it. Ooodles of corruption and insanity all around!