I don't think I have the answer you're looking for, but that's probably because a clear, perfect answer doesn't exist. But here are a few things, some of which you've probably considered. One issue is to be wary of changes. You're probably on top of this because it seems as though you're looking at fairly subtle changes in how you run. But unless you really go through some intensive coaching and training to change how you run (and even then maybe not), I can only imagine that changing your natural running will cost you more in efficiency than you'll gain with super shoes.
But the answers above that strike me as the best are ones about trying different pairs, running workouts (and only workouts) to develop feel, etc. But that's an imprecise process heavy on time and money. You might be looking for a kind of matching of shoe type to the right combination of build, pace, and mechanics. And it seems to me that a broad, systematic study would be required to provide that info (if it would, in fact, be borne out) in a clearly meaningful way.