I've been using Commander Shadow Sun as my warlord for Tau in my past few games. I found her to be a nasty piece of work as the Warlord with all the special abilities she has.
I run her with Crisis Suits, all carrying dual Fusion Blasters and gun drones. She always runs with her two special shield drones.
The amount of firepower that unit can absorb is pretty insane, especially if cover is involved. And she can give as good as she gets with all those Fusion Blasters. Her insane mobility and outflank ability really is crucial in getting her into the right place on time.
Has anyone else found success in using Commander Shadowsun?