As a general rule, the navigation is easy in the BVI, but you don't want to be naive when you are sailing into North Sound or approaching Anegada. We've had a few rain squalls over the years in the BVI that reduced visibility to less than a tenth of a mile. Thankfully, they were short-lived and we eventually resumed visual navigation.
You may be able to see the islands ahead in the BVI, but it isn't always obvious what you are looking at when it is all new to you. You need to have some basic navigation skills and be able to take a course off a chart.
Having a handheld gps plotter will do wonders for your confidence if there isn't one installed on your charter boat. You can either enter waypoints (from charts or cruising guides) yourself ahead of time or buy a chart chip for the eastern Caribbean.