Ass you point out the challenges are enormous going to Mars, nearly everything is orders of magnitude difficult to do than on earth. Apparently, just deciding to go for a spacewalk at the moment on ISS requires several days of preparation and I've heard being in a spacesuit is like being inside a soccerball because mobility is so poor. No doubt things will improve but I actually think space is too difficult and expensive for humans...best to develop AI and send it to those places (although I know if some of my space friends would strongly disagree if they were here!).