Ride (shuttle) Mag7 from the top of Gemini Bridges Road, then bail out to the Brand trails and do a lap or two on Deadman's Ridge, Bar B, and Longbranch. The last half of Mag7 sucks anyway, and these singletracks on the Brands are some of the best around.
You'll like the mag 7. Shuttle if you can and if you are going to make it a shuttle you should link it up with some other stuff as mentioned above....not familiar with deadmans or bar but a nice loop to tie into it is little canyon rim or connect. Another big ride would be mag 7 connected with the Portal trail. Here's a map of the mag 7 along with some video and pics
I camp near the gas station so I'll ride Gemini Rd from there to the far end of Bull Run, ride Mag 7 to the Poison Spider parking lot, and ride pavement/thumb a ride back to camp. Monday morning if anyone wants to join.
I'm familiar with the Brand Trails, I guess I tie that in with the whole Sovereign area.
Another big ride would be mag 7 connected with the Portal trail.
Also know as, Mag 7. Bull Run (1) > Arths/Great Escape (2) > Little Canyon ST (3) > Gold Bar Singletrack (4) > Gold Bar Rim (5) > Golden Spike(Or blue dot if you're naughty) (6) > Portal/Poison Spider (7).