BRING BACK ORION! Launch ships the size of aircraft carriers that have six-foot solid-steel plating -- DIRECTLY FROM THE SURFACE OF THE EARTH, WITH A CREW OF HUNDREDS! SEIZE CISLUNAR SPACE! Deny it to other nations. Screw democrats. Screw enviromentalists.
Travel in an asteroid would be excellent, because it would be very well protected, and be easy to expand the habitat. Of course, getting all the orbits to match is like figuring out (in advance) the pattern laid down by a Spirograph. :')