Well, the over 80cm size won't work for my doll setup. All of my doll crew represent characters who interact in the same "universe", thus for them, I stick to 1/3 scale, so that they all look harmonious with each other. My tallest (Dollshe) are 70cm, the others are all 65cm, with 2 girls at 60cm. This works nicely to also keep me from just buying anything too spontaneously (so at least I save some money!
).
That said, I certainly admire dolls in other smaller scales, and I also like the Mecha Angels and EID guys, but don't add them because of keeping everyone in the same general scale.
Also, the bigger (and heavier) the doll gets, the more difficult to carry around for photo sessions (or if they're really an unusual size/scale, harder to find clothes and shoes that fit, unless of course, you're able to make these items yourself).
I do have some 1/6 dolls (they aren't part of my other crew's storyline), and enjoy that scale very much. There's a lot of adorable dolls, clothing and props in the 1/6 size range! And they're really fun to play with and photograph.