Putting is designed to make you think. I find a great course for putting is S.A.. You will have a variety of challenges, uphill, downhill, sidehill, hard breaks, slight breaks etc.. Also, the more courses you play the better feel you will get for reading the breaks.
Memorizing putts in my opinion is not the way to play. Understanding, and reading the green is more challenging, but also more rewarding. Knowing the green layout is essential for your approach shots. Golf, is always about improvement.