There was a brief spell when I busied myself with Sudoku puzzles. However, I very quickly found that solving the puzzles required a very small set of mental tools, followed by a whole lot of tedious elimination, getting rid of dead possibilities until only the correct solution was left. My interest in doing them waned at that point, since I have no interest in the work part of the exercise - I was interested in the mental exercise.
I briefly moved on to the so-called Killer Sudoku puzzles, which use a rather different set of mental tools. These vexed me for slightly longer, being a bit more difficult. Sadly, though, once you master the mental tools that are required, it again becomes an exercise in elimination, and not necessarily the great mental exercise it once was. So, again, my interest wanes.
Now, it is fair to say that I don't solve these puzzles in the time guides they give for the task. But I will solve them all, and will do so accurately (unless I make a silly error). I could get my time down to the suggested values, but doing so would require practice, and I have no great interest in putting in the effort. Becoming good at Sudoku variants is not a priority.
By contrast, I am conscious that I should be putting in a lot more effort practicing my piping. More to the point, I should be putting in a lot more effort in practicing the very basic techniques that are used when playing, the very same areas which Ian has identified as a weakness. It is this practice, and practice in depth, that will lead to real improvement, not merely learning X number of new tunes in Y weeks. (Although, I do have to learn five or six new tunes in the next four weeks, for my trip to Italy.)
In my defence, I haven't spend an evening in the apartment in the last two weeks. I've been quite busy.