What speaker configuration for custom built 4x12?

So I decided to build a slightly oversized 4x12 similar to the old Mesa Halfback cabs. The bottom half is completely sealed (with divider between top and bottom), while the top is 2/3 closed. My main concern is that I need it to stay tight for death metal type stuff but still nice on cleans and rock tones. I'm at a loss for what to load it with so what speaker combination would you suggest?