Two commercial single wall ones are the above mentioned MH Driekt 2 and the BD Firstlight. Both use, more or less, the "bibler" design with 2 crossed poles, are super easy to set up and are TRUE freestanding tents in that you can move them rigidly around fully set up. Just stake them down or you may be fishing one out of a tree.
Both are about 2+ lbs, the latter one you can buy carbon fiber replacement poles that will take a half a lbs off the weigh and get it closer to 2 lbs even. The BD is breathable, but not a tent for heavy extended rain, the MH one is more waterproof, but does not have a zippered screen door. Both are really nice for backpacking, but the design is basically optimized for mountaineering. Both are good choices when heavy condensation is not going to be a huge issue. Both have a ton of headroom and are big enough for 2 sardines, or one as a palace.
On here 4 lbs is what we would call "heavy", even for a double wall tent these days. :-)