You know your curios are working for you when you almost never take health damage for entire runs, especially with psyker. This means you want to be at 100% toughness almost always, and return to 100% toughness asap whenever you are hit. Avoiding taking damage is the top priority of playing psyker, and you should always stop whatever you were focusing on to avoid taking damage.
The most important curio for achieving this on a psyker is a +3 stam curio combined with the kinetic defection feat. You only need the one to have enough block to get to safety from any situation. It works especially well with deflection on the force sword.
The next most important is +toughness. The bigger your toughness pool the less percent any hit will do, so it is effectively toughness damage reduction. I only run one though, which I will explain shortly.
Health is the backstop, when you’ve made mistakes you will take health damage. If you make many mistakes you will probably value health quite highly, and get stuck depending on it to cover your mistakes. I still run one though, because it gives you a buffer against instant death when you have some corruption and because I often carry grimoires. If I cared more I would only run a health curio on grim missions, but I’m too lazy to swap.
Wounds is the backbackstop. It is the ambulance at the bottom of the cliff. If you need wounds you probably aren’t ready for the difficulty you need them on and you should drop a difficulty level to practice a bit, really focus on not taking damage.
As for perks, toughness regen is the most important. Getting back to 100% toughness asap lets you tank another hit without taking any health damage. A good psyker should always be in the middle of your team and so constantly in coherency. So prioritize getting +30% toughness regen on all your curios. The second is gunner resist, because you will get shot no matter how much you dodge and slide. So then prioritize getting +20% gunner resist on all your curios.
In the final spot I take combat ability regen to knock ~3-4 seconds off the ult cooldown. It is a bit more complicated to explain why this is a great choice though, but basically it is one of the few curio options that actually boosts your offensive power. Most obviously, you can ult more often, which is great especially with ascendant blaze as it boosts your damage output. Secondly, if you have ever popped your own head with less than 3 seconds left on your ult cd, this perk would have saved your life. If you aren’t edging the limit of popping your head then your are missing out on psyker potential. Finally, warp flurry is the meta BiS blessing on all force staves because at 5 stacks it is a game changer. So being able to ult to drop peril and stay on 5 stacks for several more casts is great, and those extra ~3-4 seconds will fairly often be the difference in being able to keep the flurry chain or not.
[Edit] I don’t find block reduction useful, as +3 stam is already more than enough block potential for every situation. I don’t find stam regen (or sprint efficiency) useful, as psyker’s base stam regen is high enough to chain pushes by default and we use peril for block. I don’t find more health or toughness useful, in comparison to the value added by other options. I don’t find sniper resistance useful, as once you develop the muscle memory of dodging or ducking whenever you hear the audio que you won’t ever get hit by them anyway. I don’t find revive speed useful, because with peril blocking you can easily get off a rez surrounded by a horde wailing on you anyway.