You'll have to redraw the path and add more segments. If the path is being drawn with the Arc tool, you can change the number of segments before you start drawing it. If you are drawing that path some other way, you'll have to use a different method to set the number of segments.
As for the vertices, you can that your curved path is made up of a series of line segments. Where they meet there's a vertex. This is a place where you extrusion changes direction so the profile won't be exactly the same size as the rest of the rail. Think about in reality, take a rod and cut an angled end for a miter. The face will be larger than if you cut square across. If you've drawn the rail so it is the same diameter as the hole in the bracket, the rail will be slightly wider at the vertices.
It is entirely possible to make your model with high precision but you might want to consider the application for the model. If the audience for whom you are making this drawing is only going to look at the overall bar, these little details you're working on won't show. Maybe there's not much point in spending a lot of time on this foot rail. Will what you've drawn convey the needed information? Ifso, move on to some other part of the drawing. The bracket is probably going to be an off-the-shelf thing and the rail will be stock to fit. Unless you need a manufacturing drawing for the bracket and the rail, you might want to say it's close enough.
