Would the Hellas Impact Basin be a good site for a mission?

What percent of craters on Mars are impact craters, what percent are volcanic craters, and what percent are marr craters?

Does the thinner atmosphere of Mars mean that meteors strike its surface with greater force than they do on Earth?

Will we pick up the junk left behind on Mars??...After all the planet is being invaded by Earthlings,,,and the aliens are litterers ...Poor Martians...

Would there be a benefit to using probes that can grasp objects - especially with force-feedback - to allow for examination of the surface side of a sample, then turning it over to test the sub-surface side of the same object? This would allow sampling with the impact of a drill or other device that may change the sample properties in subtle ways.