I agree with those who point out that for worship music the rhythm is the most important factor. Having a good simple rhythm and playing the root is what most songs call for. I wouldn't feel bad about just playing the root for the majority of the songs. For many worship songs just playing basic root whole notes serves the song the best. Root/5 combinations also can work well and simple chromatic and nonchromatic chord approaches. In my experience doing much more than that can really muddy up a worship song. I sometimes play more complicated baselines but usually in the end I realize that it doesn't serve the song and I revert back to the simple baseline with a good rhythm for most songs. Our closing songs are usually more animated and then there is more opportunity to diverge.
It is WAY better to play a solid rhythm then try and do something fancy and ruin the atmosphere in the worship. Remember, its not about you buddy.