For your first or even a second visit to Death Valley you do NOT need a high clearance vehicles. There is so much to do along paved roads you will be fine with a simple small sedan. The paved roads are excellent. We are renting a 4x4 pick up truck from Enterprise in Pahrump, NV only because it is our another annual visit to Death Valley NP and this time we want to do some hiking in the areas that would be easier to access with a high clearance car. Try to relax and enjoy all this park offers without getting on less traveled and some time very rough roads.
Look up posts of Frisco_Roadrunner who many times gave suggestions for itinerary in Death Valley.
One suggestion is to go for a walk to Mosaic Canyon. It is a beautiful canyon and to get to the mouth of the canyon you can easily drive on this gravel road in a regular car. We, and many others, made this easy drive without SUV. Park Rangers have several activities every day and you may consider them too. I would like to give you more ideas on places to access, visit, hike and enjoy in a regular sedan but I need to pack today for my upcoming visit to Death Valley.
Have a great trip. Meanwhile check out this website www.nps.gov/deva