I think I will echo the sentiments of those above in that it is wise to start with the basics and just learn through trial and error. Also the guy who said "there is only a momentary best" is spot on. For a long time I just didn't get good mornings.
I couldn't use any sort of meaningful weight on them, the form felt weird and just... wasn't a good movement for me. I'd still rotate them in from time to time because the Westside guys did them but I never felt like they were really doing anything for me.
However, this spring, something in my body just clicked and for whatever reason, good mornings started working well. My form was great all of the sudden and I could feel the right muscles being activated. I did them every week for about 12 weeks in a row, got a lot stronger on them and last week I hit a huge deadlift PR, which I attribute largely to the strength I gained in good mornings.
Now in a couple months I might lose this feeling and another lift might be doing the trick. I think you gotta feel it for yourself.
I don't think that this is a dumb topic, but I think it is better to learn via trial and error than to try to predict. I believe (and have learned through actually doing them) that the muscle fiber typing tests are basically just reflective of what training you've been doing, the earth/aire/fire/whatever typing is retarded and that you can't always put a blanket statement on somebody because of limb lengths.
Case in point, I helped a buddy of mine train to walk on to a D1 basketball team. He's 6'8". We didn't throw out the back squat, we just started lower and he had to constantly work on his form. Now he's gotten a ton stronger, squats with pretty much perfect form and has seen a lot of dividends from that movement.
I also think that consistency is very important. I think too many people go through and totally switch up their program too frequently. If you change 5 of your exercises every 8 weeks, how are you going to know what is working and what isn't.
Whereas if you change say 2 things (be it different movements, methods, set/rep schemes, arrangements, etc.) every 8 weeks or so, then when you do make improvements, it is pretty easy to see what made a difference for you.