Hello Roro
[1'] She isn't greatly to be admired.
[2'] She isn't greatly missed.
[4'] She isn't greatly missing her family.
Yes, those are all fine. But a strange thing: without context, the positive versions of these sentences sound 'straightforward'. They mean what they say. But the negative versions have an air of irony – in other words, they aren't simple 180 degree negations of the positives.
'She is greatly missing her family' – she feels a little tearful when she thinks of them.
'She isn't greatly missing her family' – she spends every night clubbing and doesn't give her family a second thought. (Perhaps not even a first thought.)
(Sorry if someone has already answered this post. I haven't yet read through the tail of the thread.)
MrP