Considering all of the back pressure forcing your Turbo to spin the wrong way, my opinion is that a BOV is essential. And considering what you've just done to your engine, I would imagine the last thing you'de want is shortened turbo life. For a BOV to be cleared legally, you do need it plumbed back into your intake.
If you plumb it back into your intake, then you're not going to be wasting it at all
As it is on my car from the factory (albeit an MR2), my BOV is plumbed back into the intake pipe between the AFM and turbo inlet.
My $0.02 and happy decision making