The first thing a worship band should do is to decide on the rhythm of the song to be played and its the drum tracks.
One need not to be too rigid as to have every little notes written down. Some freedom should be given to the musicians for creativity and variations.
What each musician (including) the drummer should to is decide generally what to play and yet be flexible enough for variations and creativity.
The drum beats are like the main pillars of a song's tapestry. The drums create spaces bounded by the striking of beats.