Colin, you are a bit sketchy about what you have now ... Down here below is a Javascript that assumes you have a selection of text frames (one or more), each of which may contain one or more paragraphs. The script assigns a random font and swatch from a list to each separate paragraph. It doesn't attempt to select "pairs to match", it just uses each separate paragraph.

Before running the script, you must fill in the list of fonts and swatches to use. There is one peculiarity in scripting required: the font name and style MUST be separated from each other with a tab, NOT a space -- that is the special code '\t' in Javascript. (You can also type a tab but this way it's more clear what's happening). See the script for examples ("Impact" happens to have no particular style, so there I don't need a tab). No worries, the script will tell you if something is wrong.

Did I mention you can add as much fonts and swatches to choose from as you want? You can -- just continue the numbering (Be Friendly to your computer and don't skip numbers either).

Here is how it looks: I selected two text frames and ran my script. Then I ran it again on the same selection. Then I ran it again, just for good measures! Total randomness ensured.

And here is the Javascript (make sure to save as "randomcolor.jsx" or it won't work):

// Check selection
if (app.documents.length == 0 ||
 app.selection.length == 0)
{
 alert ('Please make sure to have some text frames selected first!')
 exit();
}
var font = [];
var swatch = [];
font[0] = "Times New Roman\tRegular";
font[1] = "Myriad Pro\tSemibold";
font[2] = "Impact";
// font[3] = "etc. etc."
 
swatch[0] = "Red";
swatch[1] = "C=100 M=0 Y=100 K=0";
swatch[2] = "C=36 M=100 Y=26 K=0";
// swatch[3] = "etc. etc."
// Check fonts
for (i=0; i<font.length; i++)
{
 try {
  x = app.fonts.item(font[i]).fullName;
 } catch (_)
 {
  alert ('The font name "'+font[i]+'" cannot be found -- please check spelling etc.');
 }
}
// Check swatches
for (i=0; i<swatch.length; i++)
{
 try {
  x = app.activeDocument.swatches.item(swatch[i]).name;
 } catch (_)
 {
  alert ('The swatch name "'+swatch[i]+'" cannot be found -- please check spelling etc.');
 }
}
// Apply random colors and fonts!
for (sel=0; sel<app.selection.length; sel++)
{
 // Is this a text frame? (It better be!)
 if (app.selection[sel] instanceof TextFrame)
 {
  // Ah right. Go over each of its text lines ..
  for (par=0; par<app.selection[sel].paragraphs.length; par++)
  {
   // .. and apply random font and swatch
   app.selection[sel].paragraphs[par].appliedFont = font[Math.floor(Math.random()*font.length)];
   app.selection[sel].paragraphs[par].fillColor = swatch[Math.floor(Math.random()*swatch.length)];
  }
 }
}

Nice addition!

Yeah that's how I learned to script as well: start with a working script, modify, then modify some more ... until you break something