[Callers] working with inexperienced bands

Hi all, I live in a relatively isolated community in the contra dance world. To the extent we have a house caller it's me. We are trying to foster and develop new callers, but you gotta have bands too. So, I'd welcome your thoughts on working with new bands. My motive for asking is, a couple of times in the last year we have had new bands come play for our monthly dance. One was a blue-grassey country band. Another was a family group playing predominantly Irish tunes. Their musical skills were fine and their repertoire was serviceable, and they did okay, but there were definitely some rough spots. New musical talent is a valuable commodity for us, and I want to set them up for success. So, how would you approach this? I'd especially love to hear from folks who have done this sort of thing before, but all thoughts are welcome. Joseph Erhard-Hudson Moscow, Idaho, USA