Oh, and also, just felt the need to add this since about a year ago I was in the exact same shoes, and haven't gotten much better since, really, and you're starting out in the busy season.....
Watch the rollers and wakes from the barges. With experience, like most of these guys have, they're not a real problem at any angle. For a beginner like me, I've learned I have to roll up parallel to them the roll in and roll out of them at shallow angles. Taking them dead on or near that can be more than a BIT exciting, when you're not familiar with the boat. A bit of throttle finesse with steering it becomes second nature.
Ray