Well it depends on your build...
If you need the recharge, spiritual works. Elec/nin tends to be a little bit endurance heavy ime, so cardiac if that is true for your build. If your endurance is ok and you don't explicitly need the recharge, musculature will give you some more damage. Nerve is the only one I think is rather worthless.
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My goal is to kill stuff fast and stay alive, very simple.
I think Spiritual is the best for it.
Any advice? My build is not complete yet so I cant post it.