All of them is very easy to do with Heroes and Henchies. Regarding above post:
Dragons Lair: BHA and Wild Blow(not really needed but helps tons) = dead dragon
Dunes of Despair: Gets tricky, but can be done without the "trick". Just use all the aids to your disposal (slow totem) and run towards boss generals at 6 minutes and 2 minutes after clearing the first attacking waves.
Thunderhead Keep: Always pug here to help with the hour long bore fest. Lighting the beacons is not an issue just skip cut-scene and light the beacons. Last 3 times through THK I had to light the beacons myself and had no problem getting bonus.