The text flow markers in text layers are sometimes annoying. Because of that, you can turn them off with Show Text Flow Marker. But note, that then you are no longer able to create a text flow.
Screen Quality of Vector Graphics allows to define the quality of vector graphics in documents. You may choose between low, middle and high. Low draws vector graphics without any antialiasing, middle uses weak smoothing and high offers the best quality but is the slowest, too. This option is used only, if antialising is turned on (see chapter 7.10.2). But attention: hair lines, that means lines with a width of 0, are never smoothed.
Show Layer Frames defines, that some layer types are always surrounded by a frame and not only, when they are selected.