I am surprised you thought there was nothing between Glendambo and Coober Pedy. I thought the landscape and vegetation changed nearly every kilometre, and was really interesting.
I think it would have been a bit different had I done it at the start of the trip rather than the end; was rather spoiled by what came before. Even the generally flat stretch from Laverton to Giles had endless subtle changes in landscape.
I still think that in northern SA, the Oodnadatta Track, while just as barren for the most part, has more interest and variety than the Stuart Highway.
That is still on my 'to do' list - hopefully l'll get there one day. I love the centre.