Well, Mummy will leave eventually. I personally don’t foresee it leaving until the Olympics is over at the earliest as I imagine they will want as much capacity as possible. I could easily be wrong but that’s my hunch.
When that time comes, the park will be in great need of an intermediate thrill family coaster. An “in-between” coaster for F&F and Hippogriff. DK could fit that though I would argue just by looking at it it’s a hair above Hippogriff in terms of thrill. That might change once I finally go on it.