I don't understand your resistance to a research base on Mars Tuco, regardless of how self sufficient it is at the start or not. We didn't chose the solar system we inhabit. We only really have one in system candidate to chose from as a practical first step to engage in this. If its worth doing at all, its clearly worth doing on Mars. The "first" human settlement on another planet certainly isn't going to be 1 star system over. And we most certainly do need individuals to live substantial amounts of their lives on Mars in clear view of all the risks. We need to see human development in deep space. We need to see the necessity of things like artificial gravity, shielding, etc. The first people on Mars are there for a 2 year stay, we need to find out what kind of health consequence that has. The ISS cannot simulate Mars. I merely view every piece of data we can gather as valuable to the big picture, the data is a gateway to taking future steps.
I'd also suggest that we are much much much further away from an economic hub style space station, than a research colony on Mars.