Unfortunately, Computer Modern (and its derivatives) are thin, since Dr. Knuth measured actual physical matrices rather than printed samples, and modern printing techniques don't get the increase in weight caused by ink gain and impression which the hot metal Monotype Modern 8a was designed for.
There are some options in the
METAFONT source for controlling the heaviness, but these aren't available when using CM-Super or Latin Modern, or a Type 1 version of Computer Modern. See Latin Modern vs cm-super? for a discussion of the differences between Latin Modern and CM-Super (which you're using).
For actual printing, you could set the MF options and generate new bitmaps to use (as a Type 3 bitmap font), but that's an awkward solution. Some computer display systems allow one to configure the settings for type display on an LCD and one can bias them to result in heavier fonts, but that's a rather extreme solution.
Computer Modern's Typewriter font is much heavier than Courier though, so I find it odd that you're explicitly choosing to use the latter.