Well I don't know exactly how it works because I didn't had enough time to test them all and I didnt' paid to many attention to understand everything but there are a lot of drills so a lot of combinations.

Indeed Arion have a good point and from what they told me and I tested it, it's important to start with some easy drills in order to get the maximum points. Starting with some easy drills then going to the others.

I assume we have to wait until a big part of members will reach the maximum level to unlock everything and then we can see the best combinations.