I guess I quite like this game ;o
Doing 1 lap GPs of a lot of tracks on expert with 19 karts is decent fun, but the challenge was a bit gone. In hopes of at least making the races more challenging (winning the GP is still easy), I edited a configuration file to reverse the starting order at each track. So rather than the first starting in first position etc, the last starts first, then the second to last, etc. At least this way, every race you got to try and get to the front.
To achieve it, in your STK installation folder edit the file
data/stk_config.xml. Look for this part
<!-- Scores are the number of points given when the race ends, order is most-points-first or most-points-last. --> <grand-prix order = "most-points-first"> <!-- Karts on position 1 and 2 will have 3 more points than the next kart; a kart on position 3 and 4 will have two more points than the next; and all remaining karts will have one more point than the next. --> <points from="1" to="2" points="3"/> <points from="3" to="4" points="2"/> <points from="5" points="1"/> </grand-prix>
Change that third line so it says
<grand-prix order = "most-points-last">
Given that it is in the configuration file I considered it to simply stand in a menu somewhere too, but that did not seem to be the case as far as I could tell.