To echo what a few others have already posted...
REI Half Dome 2 or 2 Plus depending on gear, space, company, etc. Half Dome has about 32' square feet of floor space versus 38 square feet for the 2 plus. Great ROI on both of these tents. Wife and I backpack in the 2 plus. Not a fan of the Quarter Dome. It is a little lighter but has smaller zippers, doesn't seem as durable (i.e. mesh and fabric), is more complicated to set up, and considerably more expensive.
You could always break the bank and go with a high-end MH, BA, MSR, Hilleberg, etc. Just depends on what you are going to use it for (3-season vs 4-season, etc) and how frequently.
Another thought is the bivy route. I solo in an Outdoor Research Alpine Bivy. If you've never done it before, the first couple of nights can be a little rough because you feel a little more exposed/vulnerable and might become a little hypersensitive to everything. Second night was a lot easier because I went pretty hard that day and was completely spent by the time I crawled into the bivy.
I know there has been somewhat of a paradigm shift recently with the emergence of backpacking hammocks but they aren't for me...
Hope this helps and good luck. Encouraging that there are so many gearheads on the board...