Granting incorporeality doesn't compensate for the -1 to initiative in any way; there's no logic here. A +100% increase in survivability (thanks to the ability) cannot be offset by penalties like -10% to initiative.
Added 15 minutes later
I suggest defense of 26 (-5%), health of 145 (-10%), and initiative of 10 (-10%), or even 9 (-20%). And increase the attack to 32.
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