If they're going to introduce a new 'breed' of Dalek, they might as well introduce a whole new form-factor for them. The four-legged fan variant posted up-thread is a personal favorite which has inspired my own bit of sketching and 3d modeling in the past. I'd love to see multiple forms of Daleks suited for various jobs. I could never quite grok the flying around thing, mostly because it came out of nowhere and wasn't used consistently. At least if they segment their body into legs, or seem to expend some kind of energy/time transforming and/or activating their flight, I might buy that their basic form has some sort of purpose.