To add on, it depends on what you want from your band . . . or rather, what vision GOD has for your band.
Me, I love a nice sax in a gospel band. Try to get some people who can multi-task . . . like, a guitar player who can also play sax, or a drummer who can also play bass. I think a lot of us musicians like to play more than one instrument, so stretching each person is usually no big deal.
In short, you need a rhythm section (ideally both drums and bass guitar, but definitely drums) and some lead instruments. Lead instruments to me are guitar and keys. A nice melody instrument, like sax or clarinet or bass trumpet, is always a plus . . . . especially if you don't always have a lead vocalist.
Be Blessed.