Improving maths (and other) questions when restarting or repeating.

Currently, if I were to do a certain series of questions again, or restart for whatever reason, there isnt too much variety on the questions posed. That leaves room for memorisation, which I feel defeats the purpose of practice - being able to answer/solve something even when its not "familiar". I dont really want to see the same question or problem on my restart that I did last session. It cheapens my sense of achievement. Suggestion would be to either increase the variety of questions/problems within each practice block in the units, so that they repeat less, or to use (where and if applicable) legitimate procedurally generated questions/problems to answer/solve. Keep people on their toes.