I never thought headgasket....sounds right though.
I have replaced with new - plugs,wires, ECT and harness
I have replaced with "like new" -coil pack, injectors, fpr, knock sensor (and tried to tighten down lightly to make it less "aggressive"?) <---pretty sure I read that here
I have retapped and cleaned my injector grounds, cleaned grounds on fender
My brother and I made sure all gears were timed correctly.
Fuel pump replaced within the last year, as well as filter...same as OP
But...no smoke out exhaust, ever. Not even on cold starts. Would coolant being burned cause white smoke? Also MY engine was rebuilt 15k miles ago, I know that doesnt mean anything. But its better than 100k