My question would be how high is the truss to be suspended off of the floor? If you have a high ceiling a motorized system to raise and lower the trussing would be a option to consider. It will become apparent the first time you change the configuration or relamp the fixtures - No rickety ladder climbing.
Also, for configuration and expandability, you may want to consider installing the trussing onto the floor with four posts. It stops the electric connection between the truss and the metal rafters (the need for the burlap). Most roof loads are figured for the weight of the roof to support (dead load) and temporary conditions like rain, snow, etc (live load). By installing trussing to the floor, you can hang/reset the lighting configuration as the needs change and to keep it fresh for the audience. See
"22X22 CIRCLE WITH OUTER LEGS @
Global Truss for an example. The legs can be anchored to the floor for seismic loading if required.
As to the electrical loading, the 30A circuits seem fine, just make sure the main panel can support the additional loading. The biggest problem I find at clubs, is the electrical service becomes under sized rapidly.