I’m not sure if it’s normal because I’m not very clear on what it is that you are describing.
I’m not sure what you mean by “smoothly stroked”, and I’m not sure what you mean by “where strokes are varied”.
I’m also not sure what settings you are using, so I’m not sure whether or not you have missed something.
That said, a “dot that looks like a comma” at the end of a word sounds like an issue with pen height (and not related to the other things that you’re describing). If the pen height is not set well (between physical position and settings), it can be the case that the AxiDraw carriage begins moving before the pen is fully lifted from the page, and this is what leaves the tail on the pen stroke.