This. Ive gotten some really big things into orbit, and having it all lashed together seems to do the trick. You can get a moderately sized base into orbit and beyond with a good two stage rocket with boosters. To get a larger base up you just need to three or four large multistage rockets. The problems is anything sufficiently worth sending into orbit will generally reduce you to a slideshow on takeoff, up until about the first stage is done. Due to awkward weight distribution, sas is generally of no use and you have to fly it manually, which just makes it all the more fun of a challenge, right?