remove default number of points to choose in `choose_points`
The number 10 is completely arbitrary and serves no useful purpose.
The only mode I could imagine where not specifying the number of points would be useful would be if we could somehow select the optimal number of points based on some criterion. For example, we could implement something where adding points has a "negative" weight, because it's expensive, but loss improvement has a "positive" weight, and so we would choose the number of points that maximises the sum of these weights.