You might look at three general tent lines: TarpTent, the MSR Carbon Reflex, and the Big Agnes Fly Creek or Copper Spur models. All are available in one, two, and three-person models. The Tarptent line generally will have more floor space for the same number of people; the other two lines are double-wall with all-mesh inners, which offers the best ventilation in really hot areas. The Tarptents are well-ventilated; the others are even better-ventilated, in my own opinion.

You'll have to go strictly by website statistics for TarpTent; no stores that I know of stock them. However, you can go to the stores, crawl into the MSR and Big Agnes tents (as I said in the other thread, if they won't let you do this, you're in the wrong store), and use their "feel" to judge how the TarpTents will work. (You can compare stats for all three on their websites.)

These won't be the cheapest tents out there, but they will all be in the 4 - 5 pound weight range - which doesn't rule out a 3-person tent on a solo backpack.