Still, you don't want a big tent, as I assume you're carrying this on your own. One starting point would be a Clip 3, Sierra Designs' three-person version of the Flashlight. It's $249, and weighs about five pounds. I like that sort of design because it's a two-pole setup, which saves weight. It's got 12 square feet more of interior space than the Clip 2, is five inches taller, but not much longer. You might also look at Marmot's Area 51 ($199), an unusual single-wall, single-pole design that's pretty light (five pounds) but very roomy. Its single wall is not breathable, so condensation can be a problem, although less of one with a single tent occupant. It's a cleverly designed tent.
In freestanding tents, REI's Clipper ($169) is a tall two-person tent that should be pretty palatial for one, even a big one. Weight is the same as the Clip 3 and Area 51 at five pounds. Similarly, Sierra Designs's Orion AST ($239) is also a light (yet again, just over five pounds), freestanding two-person tent. Beyond that you get into six-pounds-plus territory. Unless... you throw fiscal caution to the winds and get a Bibler Ahwahnee, a breathable single-wall tent. Big, roomy tent, fantastic views out both sides, utterly shocking price: $699.