I would call some of the churches larger than you are who have just built new buildings, and ask them for who did theirs, and if you could speak to the person who headed the building project at the church level. That way you can find out from someone who actually had work done by X firm how well they worked out.
We ended up FIRING our architect, who was also serving as our Gen'l Contractor. We would have GLOWING words to describe the company who stepped into a half-done MESS and pulled it together and got it finished, exactly when he said he would.
When you go shopping for a firm to do all this, look for someone who has already had successful experience with churches. If you were closer, I'd recommend the firm who got ours done.
I highly recommend someone local enough who can deal with the county codes; but someone with enough experience to know what a growing church is going to need is worth their weight in gold. It takes more than architect school and passing a building inspection to make a church work for the people who will come and use it.
deb