If your midwife is very experienced she will be able to cater your wife's care to suit her needs, and can predict if she is likely to have complications. If her pregnancy has been generally uneventful, then everything should be fine. Surprises can happen, but the really nice thing about midwives is they are only a phone call away.
I think the best thing you can do right now to assure the health and well-being of both Angela and your child is to be well-prepared for the event and help to keep her as comfortable as possible. Think of things like hot towels/hot water bottles, massage oil, etc. that might be good to have handy during labour and arrange for that.
