Bear in mind the limitations of your camera's sensor regarding dynamic range. There is only so much you can do in such high contrast situations like stage lighting, you will ultimately have to deal with some blowing out of the colors.
Good improvements and advice from other members here.
Sony A850 | Sony Battery Grip | Carl Zeiss 24-70 Vario-Sonnar T f/2.8 | Sony 70-200G f/2.8 SSM | Lensbaby Composer Pro | Sony HVL-F58AM
Alienbees B800 (x3) | Alienbees Cyber Commander | CSR+ Receivers | Grids, Softbox, Gels, Manfrotto/Century/Avenger stands