Another option to consider is a ghoul based on a hound – as the fastest and most mobile unit among this group.
And this ghoul will jump, but I think one of the upgrades will be on a yeti model – a large and strong monster, but without jumping.
Added 1 minute ago
It should fit the standard model; I'll take a look at what's there... I didn't quite understand; should I shrink the standard head to approximately the size of a skull so that it covers the old head, right?