You really can get used to unsweetened tea. I actually prefer it now. It just takes a little time.
When I make a pitcher of unsweetened tea, I'll throw in a bag or two of herbal tea (blueberry, lemon, etc.) along with the regular tea bags. The herbal tea gives the drink a little extra flavor.
by a little extra you mean any at all, right?
:p
I watched an old friend, who is a chef now, make a drink on youtube. He put some lemon and mint down into the ice and crushed them a bit before adding the liquids, to release their oils. I started doing that with my teas, using really well washed sliced lemons and limes, along with mind leaves and a bit of sugar. Not just dropped in, or squeezed, but crushed in the ice. Very tasty.