nicb
I agree with most of your thoughts, although I am a firm believer in getting the fish to "enjoy" eating your bait. Once they do that their guard is lowered so often a simple conventional rig will score. As a result I end up the majority of the time using Bottom Baits.
I did have an "In yer Face" brightly topknotted Snowman on one rod Sunday as the fish had been spawning and I wanted a visible bait to attract their attention as they left the spawning area, but this is a rarity.
I do not rely solely on one rig. I do experiment and try out different things, but often find that I end up going back to my simple size 6/8 Line Aligned Braid Hair Rig, which works on the majority of waters I have fished.
I will state though, that I do not fish heavily fished pressurized waters. If I did then i would probably experiment more.
As for going on, from the standard hair rig, then the next step is the sliding hair, the D-rig, Savay Loony tube extension, and so on.
Don't get me wrong I know there are many more up to date rigs than that, but these are just progressive steps on from the original concept of the "basic" Hair.
How many fish would we catch just by going on by going back in time to some of these rigs?