If you are on a team with unlimited resources pursuing a composite monocoque design, the only things that need to be constructed from steel tubing is the front hoop, main hoop, and main hoop bracing... is this interpretation of the rules correct?

Nice screen name...

I wouldn't know about unlimited resources, but for a team of students working hard to get materials and some mold making / autoclave time donated, yes, that's about 15 pounds of steel you have to add to your tub. I think the front roll hoop must have bracing made of steel as well, and you must have a good SSEF showing that these items are well-fastened to the tub, with large foot-plates to prevent punch-through in case of a rollover.

The front roll hoop does not have to be steel, just "closed section metal tubing" and not a composite material. Section 3.3.3 of the 2005 rules (beginning on page 20) outlines what materials may be substituted for steel. Our last generation monocoque (1999-2004) used an aluminum front roll hoop with an aluminum bulkhead at the rear for a structural member to bolt the rear roll hoop. Our new generation chassis still uses an aluminum front roll hoop, but we have replaced the bulkhead in favor of phenolic hard-points located between the inner and outer layers of carbon fiber, placed among nomex honeycomb core, as hardpoints for the rear roll hoop.