Drove to Flinders Range, wanted Lake Torrens but was discouraged by wife and friends
Originally wanted to also visit Coober Pedy (wife was in an opal craze phase back then) then up to Uluru
Part of the plan was to go all the way to Alice Springs with the rental on a two location stop then fly back
But it was really much too expensive
The route was also not as well defined (checked the topo maps); I had thought/and think there is a path that leads up to Lake Eyre, cuts through and then back down to Roxby Downs and the Stuart Hwy. You'd do much better asking on the Aust Outback/4WD/trail forums; it's quite a developed community.
It's not going to be a short trip though, going to chew up a lot of precious miles on that route going up and down then back up again.
A 4WD, jerrycans of fuel and lots and lotsa water are a must; knowledge of the machine ... and the worst, since it's a rental, is figuring out how to get spares
I contemplated buying a repair kit when I reached Aust which is partially doable, but certainly adds to the cost and it's throwaway $ (didn't plan to bring it back with me)
Loved the Yorke Peninsula, missed out on the Eyre Peninsula, which from what I've read is quite the gem too
Then again, the initial trip was to drive the Nullarbor too so...