There are a couple Eureka Mountain Pass tents that are exactly what you are looking for. I have a 2 man that was the prior model, and I bought it as a 3.5 season tent for 2 w/ vestibule and free(ish) standing. If the new blue model is similar, you're good to go.
Mine weighs 6 lbs or so all out, though I do have Ti stakes for it, which saves 4 oz or so. It can be zipped up real tight with no drafts, or opened up pretty good. The vestibules need stakes, but the main body of the tent doesn't. If you couldn't tie it out at all, it would work, but not as well, because the outer wall would lay against the body, and you would have no vestibules.