I do think that if Scorpion Express has died a death, as many infer that it may have, a new kiddie coaster would be a logical replacement.
For a park of their demographic, I’ve always been surprised that Chessington don’t really have a bonafide kiddie coaster. Even Scorpion Express itself is arguably not a bonafide kiddie coaster in the same way as, say, Octonauts at Alton Towers. And if Scorpion Express were to be removed, Chessington’s lowest height restriction coaster would be Vampire at 1.1m. That would give them the least accessible “first coaster” of any of the Merlin parks, which would be a surprise given their target demographic of families with young children. Even Thorpe Park, which actively targets itself more towards older guests, has a 0.9m height restriction coaster in Flying Fish (which is actually a clone of Scorpion Express, so although not a bonafide kiddie coaster, it is a relatively widely accessible family coaster).