Quite apart from your dismissal of the problems of getting a man to mars as "higher risk and cost", rather than "as yet, not proved to be possible with the technology we have available", you seem to have missed another fundamental point.
The devices that get sent to Mars aren't built in 24 hours. The design is done exhaustively, and then reviewed exhaustively, as well as being modeled and redesigned. This design is then built, painstakingly, with stupid attention to detail, very slowly - since every stage is tested extensively as well.
In the end, the stuff that gets shipped up probably WAS designed 5 years before it was shipped up there - explaining the "pedestrian" development.
Considering the turnaround involved (probably in the order of 10 years from starting to design the device to it actually being on the surface of Mars - is it really fair to compare it to any sort of research on Earth that takes minutes or even days to do?
I work in IT. Some things take 5 minutes to test - these I develop quickly. However, one of the things I'm working on takes 1.5 hours to "run", and therefore development on that takes a LOT longer - and that's just a moment compared to what these guys have to deal with.