/6 build

Does anyone think this is a good build? .

I don't.
Your parts are all wrong. That cam would probably work for a mild turbo build, but is way too mild for a NA slant. I wouldn't even use that cam for a turbo, unless I already had it on hand. If you need to buy a cam anyway, order the right cam for what you are doing. Step headers are only needed for a full tilt race motor, and certainly not for a turbo motor. For a NA motor, with a decent cam, you need compression, for a turbo, not as much.
Like Bill said, you need to determine what you want to do with the car/engine, then build to that goal.
As for the EFI, why the buick setup? It would probably be easier to get an aluminum intake manifold, weld in injector bungs, buy/make a fuel rail, and use a mega squirt or other after market ECU.