Here's the reason the two-piece rotor w/ aluminum carrier probably wouldn't easily work with a Speedhub: check out the clearance between the rotor bolts and the black piece to the left called the external shifter (descending from the axle to the bottom of the photo).
For reference, the rotor in the photo is 1.8mm width. There's very little clearance. In fact, I've tried to shim a rotor out, away from the hub, and the rotor bolts contacted the external shifter. By countersinking the mounting holes (they're standard chainring bolts), there may be a way to make it work.
I haven't measured the Formula aluminum carrier, but in photos of the Hopes, it appears the carrier is the width of the rotor plus the bolts, and that definitely wouldn't fit this setup.
In any case, I'm not going to fuss with it.
BTW, the rotors are cut with lasers. I presume the aluminum carriers are forged, as this results in a much stronger structure than machining.
