I recently did a crappy AI for poker chip too (around 5h of work) and went 150/1241, that's 500CP == one very hard puzzle. It's still isn't much, and that is because the formula is the following:
which means whoever is first at this puzzle only get 1241 points currently.
So to get more points easily (around 1000CP each is doable) you should focus on the puzzle with more than 2500 contestants, example again from my score:
Back to the Code - 952/3148 = 235 CG
235 CG for such a crappy ranking
TL;DR: Multi games are much more rewarding than any other system for now, look at the points of top contestants and you'll see half is the multi game, half is the achievements. So 7 multis == dozens of solo games.