George Nicholson wrote...
....
3) UsedRange & xlCellTypeLastCell take into account formatting, etc.,
but
not Pictures or Charts on Worksheets. For that you could use
Sheet1.Shapes.Count = 0

Another thing to consider is worksheet-level defined names. Check

SomeSheet.Names.Count = 0

Maybe safest to check that the .Count properties of all collection
objects that have Worksheet as their parent class are zero.