I really like the drill you suggest. I bet if you turned most drills into statistics and then tracked them over time, it really would make practice more fun.
How about this idea (based on the ideas from above and combined)
9 distances (Putts; 10', 15', 20', 25') (Chips; 10', 20' forward pin, 20' back pin, 30' forward pin, 30' back pin)
The goal is to track how many up & downs you can get. For putting, the goal is to not...