One of the problems with developing a product for non-profits and churches is that you run into needing to have your offering assessed by a committee before a decision can be made.

Rather than one business owner or individual being able to say yes, what happens is someone will need to propose the idea to the board/church council etc. and then it will be debated, and perhaps might get the go-ahead. More likely than not however someone in that group will have some objection, or say "my nephew is good with computers - he can do that!" It's going to be a very high-touch environment to work in, and probably not great as a side project just because of the time you will spend.

Could you perhaps target people who design sites for these organizations? They are already doing the high touch sales - perhaps you could come in as the technical partner. That way you'd be selling the reassurance of all the backend technical support, the backups, the CDN etc. but not dealing directly with the end customer but instead hopefully a local web designer who has several of these types of clients.