Two protocols I've used effectively while still training in the set/rep format were EDT (Escalating Density Training) and Density Training. The former was developed by Charles Staley and the latter by coach Ethan Reeves. Both protocols basically involve doing more and more work within a specific time period. An EDT example would be to select two 15 minutes time periods for your training session. In the first 15 minutes (A1) you might do C+P and Pull Ups and in the second 15 perhaps Front Squats and snatches. Each sessions goal is to beat the total reps per 15 minute time zone. Once you have upped your reps by a certain percentage you increase the weight.
My limited experience with GS training has got me thinking that one of the aspects that make GS so effective is indeed the concept of keeping time static while manipulating the amount of work you do. In each session the goal is to break your PR from the previous session. What is great about this way of training is that progress is easily measured and your training sessions tend to be short and focused. Also, there are no questions left unanswered when it comes to deciding when to move up in weight. Once you can perform a solid 10 minute set of let's say 10 jerks per minute you can consider progressing to the next size kettlebell.