During one soundcheck, test with both setups (quick 1 minute adjustments lang naman yun) if you can hear the hats adequately from a distance (like, from the back of the church). Have someone hit on the drums and cymbals while you listen at the other end of the room. The test should take a total of 5 minutes.
If you don't have 5 minutes, I think you should retain the close micing if your cymbals are a brass model (Planet Z, Meinl Headliner, etc)
or go ahead with placing 2 overheads if you have bronze models (from Zildjian ZHT, ZBT or ZXT, Sabian B8, Paiste Alpha, etc, and higher models). Reason being brass models do not project as much as the bronze models.
I guess it will depends na rin on your musical intentions. My suggestion assumes that keeping the beat might (hi hats) be more important in getting crowds to sing than song climaxes (crashes). On the flip side, I've heard some gigs in some churches wherein the beat wasn't as important as the crescendos, because the songs they used were dramatic and, um, Evanesence-ish.