Well, you are competing with a behemoth with Zondervan publishing and The City (http://www.onthecity.org), and your pricing seems to be only marginally better (for hosting.. I just now noticed the part at the bottom about being able to host it yourself for free). Do you know how many people are using it for free vs. paying for it? You may want to re-think the open source model, though I can't imagine there are TOO many churches that would want to bother hosting it themselves.

You may be better served finding a smaller niche and doing it really well, rather than having such a huge feature set that may be overwhelming to people on their first visit. You don't necessarily have to pivot to something less social, but I'm sure you can do some research and find out something that you already provide that church staff think could be much easier, and make that an emphasis.