My view on terraforming is that we need to land first and research. Any kind of terraforming is far into the future. I still think it is important for us to go to Mars despite me thinking it will be hard to terraform for that reason. We need to make our own little habitats on Mars and learn about it. Olympus Mons is my only point of interest on Mars because we could learn about its interior much faster than just drilling into it. Landing would be a problem though and finding out how to climb the biggest (not active) volcano in our solar system will be hard.
Well, even if we had terraforming technology, that's a process that would takes thousands of years if done on a planetary scale, so isolated habitats would probably be the cheaper and quicker way to do it.