When this thing gets there, how is the sky crane gonna know where to drop the rover? For all that it matters, it might drop it right on the side of a rock and the rover will tip 90 degrees and go belly-up!
For that matter, what sort of measurements are taken, if any, by the cruise stage to precisely orient the capsule for targeting a specific crater? And does the entry module do any sort of active course correction up to the point where it lets go of of the sky crane?
AFAIR, you select the landing ellipse already in a way, that you don't land in rough terrain. The rest of the targeting is also simply ground control. There is no fire and forget for Mars Rovers yet.
There are possibilities to make the landing radar and cameras select a good landing site automatically, but at least the radar part would inflate the rover mass a lot, since you then need a much more powerful and much more precise analog part for the radar. (Optics are more unreliable, but can be done just by software, that is why cameras had been used by previous Mars rovers for aiming for a good landing site and cancel horizontal velocity)
As long as even parachuting human soldiers can't always tell properly where they are landing and what landing site they are actually aiming for, I don't want to expect this from probes for relatively unknown planets.
What can look perfectly flat can be the most annoying place. And what looks really jagged can be a perfect landing site.