I’d consider missing out the bit of Woodhead / Snow Road after/before Cut Gate. You can reach Dunford Bridge with cunning use of bridleway / TPT then use the quieter road from there to the Longdendale Trail rather than ride on the main road which is quite unpleasant/dangerous. The ruts on the Snow Road are so deep that it’s very hard to actually ride uphill. You can cross the road just along from the Flouch Roundabout, head up the road then take the bridleway that cuts across to the disused railway line/TPT.
There are a fair few campsites around the area – Hayfield, a couple around the Hope/Hayfield area, two in Edale plus a couple more nearby and one at Crowden off the Woodhead. Somewhere below Cut Gate on the Ladybower side might work for camping if you’re discrete, depends on whether you need to have water on your doorstep. On top of Cut Gate would be atmospheric. The rest of it is relatively, erm, not wild I suppose you could say.