If I could only have one tree stand, it would be a Lone Wolf Alpha Hang On with Climbing Sticks. A climber is lighter, but limits you to straight trees without branches.
Climber, I like the Lone Wolf Alpha Hand Climber
What I use mostly nowadays is a saddle, cut down sticks, and a climbing aider. Most packable and the lightest, allows you to climb pretty much any tree. Not as easy to get set up though, harder to get used to.