Apparently 100' wide by 65' deep space with a 15' ceiling, but details such as how much space is above the ceiling, how much of the 65' depth is stage/platform versus listener space, whether the listener space wraps around the stage/platform, the room acoustics, whether the system is envisioned as being mono/stereo/LCR, the services themselves and expectations for the system performance and so on can all be relevant factors in what system solutions may or may not make sense. Even factors such as ambient noise levels from the HVAC system could be a factor as lower ambient noise levels are usually not nearly the concern for a bowling alley that they are for a worship space.
This is very generalized but in situations like yours I believe there are typically two approaches. One is to define the goals for the space and systems and then assess what is required to achieve those goals. The other approach is to focus on how to best apply what resources you have to the new space with the resources available greatly defining the approaches then applied and the results possible. Trying to expand or adapt what you already have may or may not be an effective solution if you have any certain expectations and in some cases can become a matter of throwing good money after bad by spending more money without achieving your goals.
This is all why it is typically so difficult to offer specific recommendations for system designs via forums, there are often simply so many potential factors involved to effectively consider and address in a forum format, not to mention often more than one 'right' answer. Ryan appears to be contacting some professionals and I hope one of them will be able to help them successfully achieve their goals. I would be interested to hear how it goes.
