I'm about the same size as you and I gave up trees several years ago. I now use a pop-up ground blind and haven't had any drop-off in my deer harvest. In fact, I seem to be killing more with closer, easier shots than when I used a tree stand.
Tree stands are great and I would use one if I were a bit trimmer, but ground blinds have a lot of advantages too. Faster to set up, more comfortable, no need for a tree, quicker to move if you realize that the deer are somewhere else and sent containment.
Again, I have nothing against tree stands. They are the best way to hunt many situations, but ground blinds are a legitimate alternative.