That small detour by Zabriske is easy.
Last I was there west side road was easy. Harry Wade road was easy to Saratoga Springs. Cut off by Ibex Dunes was listed as deep sand... was maybe 6" max just filling the tracks.
Johnson canyon has a crux about midway that needs high clearance jeep or a spotter to get over some very large rocks. I parked and walked in.
Road to Crankshaft Junction is easy but watch your speed in the dips.
Road direct to Chloride City had some difficult spots. Narrow and steep.
Mahogany Flat was easy with no snow.
Skidoo and Aguereberry were easy. Although Skidoo has a long stretch of one lane I was happy to not meet any on coming vehicles.
Next trip I want to get to Warm Springs and Eureka Dunes.
http://npmaps.com/wp-content/uploads/death-valley-backcountry-roads-map.jpg