Moon dust is super nasty. It is composed of particles of shrapnel, essentially, created during meteor strikes. The only bits that aren't all sharp edges are the blobs of glass from the portion that was thrown up as lava. You want to stay away from it as much as possible.
And when exploring a new world, you need to be able to handle all terrain, from steep crater walls of loose material, to fields of boulders, to deep crevices, to ponds of deep fine dust.
Also your vehicle has to do everything. It will have arms so it can do all the manual labor needed to build, manufacture, repair, prospect... whatever comes up, most of which won't be very predictable.
So the rovers for Cernan's Promise will take the ATHLETE rover model one step further. They chuck the wheels altogether and walk around, and some of the legs also can be arms. (I can't help but think that is the eventual idea for ATHLETE too.)
I rather like this video for getting across what i mean :)
The spider-bot that wants to be a rover
My thought is to reduce that concept to 6 legs, put mechanisms on two of them so that the bottom joint folds out of the way and hands are deployed for doing any kind of work.