Personally, the Base for me.
I am not good enough to notice the lighter wheels.
I can live without LED headlights, I am not sure if the illumination is superior but in any case, I don't go riding out in the hills at night because I really don't want to run into a big kangaroo.
I am not convinced that the electronic suspension adjustment has any real value. Adjusting suspension in a car is normally a time consuming job, especially gaining access to the rear shocks in many cases, so remote, electronic adjustment makes sense.
I have had several high performance cars with adjustable suspension and I am at the point now where I just leave my GT3 in a normal setting for all road use and stiffen it up when on a smooth race track.
When I do a track day on the bike I spend a bit of time the night before removing the number plate, mirrors, setting the dash up, etc, and it is hardly an inconvenience to have a piece of paper with a few settings written down and rotate a few clickers at the same time. Because of the car thing, there is no novelty factor for me also.
I keep hearing very positive reports on the Base suspension as well so I just can't see what is an $8,000 premium for the S being worthwhile.
I will be selling or trading the bike in time as well and the depreciation hit will be far less, makes me feel happy spending 2-3k on mods to individualise the bike to suit my tastes.
Unlike in the car world, we get exactly the same engine on the Base model as well which I think is awesome.