I do have an iPad on which I've been using the 11 beta for the past few months and I love the new multitasking support, but is it really big enough to warrant a major version bump?
You already could run two apps side by side in iOS 10 (I was a pretty heavy user of that feature, which is incidentally also the primary reason I opted into the beta), it just wasn't quite as flexible. Drag and drop is new, for sure. I suppose I haven't used it much so haven't really noticed it.
The dock seems like a small improvement over the old dock, added because of the better multitasking.
They're great improvements for sure, but they still seem like incremental improvements to me.