There's no accounting for taste.
I've always liked "quirky" even "odd". (Go Figure!)
1) I really like the R1200S. The shape of the tank cover/fairing is a bit "off", but nothing a graphic couldn't help (the red/silver one is better looking to me.) It looks elemental and personifies "form follows function". I could see myself owning one.
2) The K1200S leaves me a little cold. Just nothing special about it.
3) Ditto for the new K1200GT - might look better in person or in a different color/trim.
4) OTOH, I like the K1200R. But that new Aprilia (Tuono?) looks thrown together.
5) The R1200RT doesn't push any buttons - the bulbousness (almost cartoonish) of the R1100RT took a while to grow on me, but I now prefer it.
6) The R1200ST is one hell of a package, but the front end treatment is too odd even for me, and I feel there's no real market for it.
All in all, BMW needs to do SOMETHING to increase market share - at least they're not stagnating.
I no longer have it, but THIS is what a BMW should look like: