Deep Borer creates Brown for War, Banshee fills War and Borer. Borer acts also as a frontline tank for the team. Star Gazer is merely there for her Empowered spell, as casting her often hinders the Banshee.
And for the record, I do know how much time means for you top guild members, it's just something I cannot truly understand. At least I cannot see the fun in this.