How do I get comfortable with the features on new diagnostic equipment?

You are handy with your tools, and that is the foundation that matters most. The new equipment with its unused features is not a gap in your ability. It is just newer than your habits. There is a difference between not being able and simply not having gotten to it yet. Most people use a fraction of what their tools can do, and get by fine. But the features you are ignoring were built to save you time or catch what you would miss. The block is usually not difficulty. It is that learning them feels like a detour when the old way still works. It is worth the detour. Pick one feature you have been skipping and spend twenty minutes with it this week, on a job where mistakes are cheap. Just one. Once it clicks, it stops being a menu you avoid and becomes a tool in your hand. Then pick the next. That is how the whole machine slowly becomes yours.