The default one is Shi-choo. I actually think in the basic forms Makashi is the most useful and you'll feel it when fighting Nihilus. His defense seems much higher than the other two Sith Lord, especially if you install mods that increases difficulty.
Battle meditation is good but it only lasts 20 seconds. I usually let my teammates do such work. Give them such powers as Battle meditation & Master Valor & etc, and set them to Jedi support.
Since I usually play LS I do not give my teammates a lot of DS powers. The exile has tons of FP and alignment penalty does not matter, but alignment penalty for the exile's teammates can be quite a pain.